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Say Goodbye To Your CD-Rs In Two Years?
Little Hamster writes "According to an article on cdfreaks.com, a test done by the Dutch PC-Active magazine showed that among 30 different CD-R brands tested, a lot of them were already unreadable after twenty months. This is shocking, and makes me wonder how should I backup my data, photo and music collection."
No, that more like: Real men don't backup their backups, or don't backup the backup of their backups, or don't backup with blue-ray lazor.
The CD is an inferior storage technology that has propagated due to 3 reasons IMO.
1. For the average person, a file is in some way less real if it is on a hard drive, and more real if it is on a CD, where it is a physical object they can touch.
2. Familiarity with CD's due to long term use on music CDs.
3. Vastly superior marketing to hard drives.
Removable hard drive bays should be standard on all PC's. Once you are used to these, the Hard Drive is just a Cartidge to plug into the PC. Data is easily backed up, and a Hard Drive in closet is safe.
Hard drives are faster, take up less space, and are very cost competative with CD's. I am unclear why CD's are popular with the tech savvy crowd. It's an inferior storage technology.
HenryJamesFeltus.com
Another endless blackhole of money.. for a good drive anyway.
The unofficial
I tend to keep a lot of my recorded CDs on the floor of my car, rolling around loos.
Is that not an optimal storage space?
..........FULL STOP.
You can buy special transparant stickers for that. They cover almost the whole CD. You need a tool to stick them on properly. See here.
-- Cheers!
Those paper CD labels that you can print out and stick on are starting to sound extra good. Surely adding a layer of paper on top of your CD will help protect it.
Article CD-R Rotting
Tuesday 19 August, 2003
CD-R's unreadable within two years
Sampling delivers disturbing Results
Valuable information on a cd-r are in practice not durable. From our real-world test to be published in the September issue of PC-Active, it turns out that the data on a cd-r can become unreadable within two years. The chance is good that the use of certain brands of cd-r's important personal information gets lost.
As a reader of PC-Active you likely know, we tested a large number of cd-r's in 2001, and published the results. Our tests already showed that new cd-r's sometimes did not meet standard quality requirements. For two years we stored the thirty different brands we tested thoroughly that year in the original packaging in a closed cupboard. For the Article 'CD-R Rotting' we again subjected these disks to a test with a professional cd-analyzer which at bit-level determines the state of the cd-r.
[IMAGE (November 2001 - Now)]
On this image you see the exact same cd-r. On the left are the test results from 2001, and on the right the same cd-r in 2003. The colors indicate the seriousness of errors in order: white, green, yellow and red. Respectively, "good readability" (white) and "unreadable" (red).
The test shows that a number of cd-r's were completely unreadable and other cd-r's had partial readability of the information. Data that was put onto the cd-r twenty months ago had become unreadable. This was on cd-r's from known and lesser manufacturers.
Generally assumed is that cd-r's are readable for ten years at least. Some manufacturers even claim a storage length of a century. Our sampling shows that there is a lot of rubbish on the market. We have found cd-r's that should never had made it to market. It is possible that we are talking about dumped batches. It is unacceptable that cd-r's within barely two years have become completely unusable.
In the September issue of PC-Active, that will be in the shop on august 22, the shocking results are exhaustively described. Next to the possible causes associated with the loss if data over time, we also supply valuable tips to secure a writable cd for the future. Additionally, on the free cd-rom a program exists to determine for yourself the state of a cd-r.
PC-Active September 2003
(from August 22 in the shop_
EU 6.99 (including free cd-rom)
Remarks/Questions? webmaster@pc-active.nl
|>>?
>> On the free cd-rom there is also a program to discover the state of a cd-rom for yourself.
C'mon, Dutch people, you're just begging for it!
See ya when your fancy flash memory you got pitched in will stop working because its state will be burnt after 100,000 state changes (including reads!).
...and I have heard this, too! all the *not-illegal* backups of my audio cds that I listen to in my car are damages within 1 month or so. This, despite keeping them in a cd wallet :)
Of course, since cds come cheap, I dont mind throwing away the scratched cd and burning a new one. But what about the environmental cost? 3 -01-13-ct-cdcare.html
btw: I found a decent link for taking care of cds:
http://www.aarp.org/computers-howto/Articles/a200
People have already posted they've had write-once CDR media last for years; I myself have media I created nearly a decade ago which doesn't show any (obvious) signs of degradation; admittedly I can't see in that cool color spectragraph they've produced (how did they make that, anyway?).
;) but my original 2^2 writer still works everywhere, including DVD players and portables (and, more importantly, on other peoples DVD players and portables). My own experience suggests that the burner is the more important factor then the media -- you can spot bad media right away because you start producing coasters at a higher rate.
The only problem I've observed over the last few years is problems between CDR hardware vendors. People bring me something they've burned on their new 52 speed writer and it only works on their reading hardware (or, more accurately, doesn't work in mine
If the price for faster burns or newer vendor equipment is a short(er) media shelf life, I'll stick with my original stuff and grow a beard instead.
"Please discuss this subject in our Media Forum."
Damn, your're right!
Does DVD-R last longer? Let's see, I'll need about 200 blank DVDs...
Hay, last time we kindly asked that Linus Torvalds guy to give credit where credit is due in that Lunix IP issue, he said that I was a greedy man who was injecting crackle, and thousands of self proclaimed hackers attacked me and my conpany. And the only thinbg that we asked for is a tiny 699$.
So the parent poster can go ahead and not give credit where due, the quote's "author" doesn't bother either.
IP law confuses me. I am persuaded slashdot readers who read this sig now legally owe me 699$
Now when ISP's are suboened for records, they can just hand over a CD. It doesn't work? Oh that's funny, it's the only copy we have. Personally I think the best way to save information is by engraving it on titanium and storing it in a pure nitrogen atmosphere in a vault.`
If you store your warez (yeah.. yeah.. tell me what else might make you care about the life of a cd than warez... blabla...) on CD's then make sure you share the stuff with local friends. They'll will gladly copy your stuff. And when your CD's are broken - They'll gladly return the favour. That's it.
I can easily beat that. I can still read data from the floppies I wrote using my Commodore 1541 diskdrive connected to my trusty C64. That was around 1987. So these floppies are 16 years old!
-- Cheers!
I have 7 year old CD-R's which still work...
The floppy disk business is a good example of what can happen when media and drive manufacturers are willing to do anything to cut costs. Floppy disks used to be pretty reliable if not abused. Bad disks were rare. With today's drives and media, the good disk is the exception.
Mea navis aericumbens anguillis abundat
I still have a bunch of MP3 CDs I burned in '98 and '99 and they all work fine (except for the I spilled Guiness on). And I have a data CD I burned in early '00 that I read the other day.
So, my data points tend to contradict their thesis, so, who knows, but don't pull your hair out.
You can do the experiment, but you will need a cheap-o-media try burning at 1x and then at the maximum your CDR drive can handle, and try it on a variety of CD-ROM drives, the odds that the 1x copy will be readable on more drives.
I still have a SONY CDR burned at 1x in 1997 ! and still works just fine. (but useless old software anyway)
I've been using Fujitsu DynaMO and GigaMO drives for a few years and found the drives and media reliable. Does anyone know how Mageneto-Optical disks stack up against CD-Rs in terms of longevity? I would imagine that MO disks would fare better...
Q: "Why do sound techs say 'check 1, 2'?"
A: "Cause if they could count any higher they'd be lighting techs."
I agree.. Slower recording speeds will usually improve the contrast ratio of the resulting recording.
One can confirm this by making several cd-r's writing at different speeds using the same type of media, and then visually comparing the cd-r's data surfaces, (For recorded areas, Darker is better).
A fair number of CD recording programs DO NOT have a VERIFY cd-r contents option after a burning, and is a major pain in the ass. This problem got me good when I used some 12x Office Depot media for saving some TV show mpegs. Bad move, :-(
I found out months later, that 50% of initial recordings had one or more non recoverable bad spots.
Nero is the only mastering program I know of, which will verify cd-r contents after burning :-),
:-( .
But it doesn't do it for all recording formats
This is of particular interest to me as I am returning to live in Mexico again on Thursday and will again have to contend with the CD Eating Fungus which wiped out a good portion of my CD collection last time (at least now I know some ways of protecting them).
I had hoped that those protections would extend to CD-Rs, but that won't be sufficient. Tape backups are expensive, per megabyte, as well as more difficult to manage for the average (and even above-average) user in a personal computer environment, than CD-Rs.
What's a good alternative for those of us that need long term (like 5-10 years) backups of data. I have things, such as writings, and pictures, that I would like to keep stored long term on a medium that won't be unsupported or easily damaged or susceptible to deterioration?
I wouldn't mind having to re-backup to new media every 5 to 10 years to keep up with technology, but I mind having to backup every 18 months just to avoid deterioratin of media.
Same experience here, some brands sometimes don't pass the year alive!
e s/recover cd.sh /. inserts, if any) :)
To try to recover the most of possible from cds (in data mode only), i have written a little shell script, basically it reads byte per byte (i know i should use blocks of 2048 but that was complicating the rest), if it fails on a reader, it asks you to put the cd in another one, etc
Some readers can read parts of damaged/old cds better than others etc... 2 cd readers required!
here is the link to the script:
http://lethalwp.dyndns.org/~lethalwp/fil
(suppress the space
i won't update the script any further.
Since these guys (those who make CD-Rs) are leading consumeers on to believe that CD-R's will last basically forever, they have really been acting fraudulently here.
social sciences can never use experience to verify their statemen
...upload all you warez and divide the account price through your friends. You can stream the warez and movies from that site then.
Make sure you avoid the US. They'll look into your private stuff and delete it. Russia and China are much better, cheaper and discrete.
Does someone know if this applies to DVD-Rs too?
How long before they die?
Can you tell me what's wrong with your site? I can't access your wonderful products and the latest news from your fight against the Lunix IP thieves!
Does anyone know where I can get the software they used for the test? I want to see in what state my CD's are in.
-- Cheers!
If you're on the Mac, the Finder's built-in burn verifies, as does Disk Copy, though, to the best of my knowledge, iTunes does not, but it will terminate on a bad burn and let you know about it. Roxio Toast also verifies.
Option-Shift-K.
I had a floppy disk sitting in the "pencil pocket" of my backpack for a year without the metal slide cover, and it still worked perfectly even with the pencil lead coverign the rest of the disk. That's why it always confused me how so many people managed to have bad floppy disks for us to recover at school. :)
another bad one: high-val (sp?)
I've had more failed discs with this one than any other of the freebies.
I second your Kypermedia... Never had a problem for 3 years (Not counting the disk I overburned w/ a corrupt video file)
Only proves that statistically your experiences mean _nothing_. One can smoke 3 packets of sigerettes a day for your entire life and live till 90 and die of old age. We still know sigarettes are bad for your health.
And yes, I've lost dozens of CDs that I wrote 5 years ago, that never left their cases and never have been in direct sunlight. I checked them a couple of weeks ago and about 4 out of 30+ still had salvagable data on them (but reading speed dropped to a crawl!). Most of them were some kind of no-name brand though so I had no high expectations of them anyway, but 5 years does seem very short.
Its also a fact that coating the CD surface with magnetic green magic marker ink will extend its life by 10%!
-- "I can't tell the future, I just work there." -- The Doctor
Too bad they didn't give a list of brands and manufacturers; that would've been good to know.
... the Mitsuis at up to $5+ per disk at times). Unfortunately I
believe they dropped off the CDR market since I can't seem to get a hold of any
of theirs, save some which is rebranded under a different name... which you
really can't find out until you pop it into the CDR drive to ID it.
I believe Taiyo Yuden made a well-stabilized cyanine die that was supposed to
last long as well.
I can't say much about the stability of the pthalocyanine dyes today, especially
all those coming from the cheaper manufacturers (Ritek, Prodisc, etc). It
doesn't seem like you can even find gold pthalocyanines anymore these days, or
heck, even gold cyanines. I don't know much about the azo dyes though.
Back when you could still get them, I burned all my important data onto Mitsui golds. They seem to be working still, after sitting around for 5-6 years. Similarly with the Mitsui silvers and Kodak silvers. All these used a pthalocyanine dye, which is supposed to be more stable than the cyanine (and cost more
Which brands are good today? That's rather hard to tell, since even within a single brand you're probably going to find a bunch of different manufacturers, unless you're buying one where the brand is the same as the manufacturer. I've seen tons of different manufactured Sonys; Taiyo Yuden's and Mitsui's showing up as Memorex's (very rare, most of the current ones are Prodisc I think and I've seen a lot of Riteks in the past). 'Made in Japan' seems to be a good sign though, instead of 'Made in Taiwan'.
Personally, I save the cheapo ones for throw-aways. Burn to listen in my car for a while, to mix and match and avoid wear and tear on originals. Scratching them up really doesn't matter, they're not that critical. Anything important I try to keep on (supposedly) more long-lasting media, and that gets handled with care. So far, 5+ year backups have been brought back up and data read without any problems. Whether that'll be true of the more current disks in another 5 years I really can't say.
-- Silhouette
I never back things up to CD-Rs. Ever. Mostly because I am too lazy to bother.
So I've opted for RAID instead. I have enough confidence in WD (once the drive has been shaken down for a month or two) to trust RAID 0's completely.
Right now I have a 4x80g WD-SE on my 2500 Athlon Linux machine, and 2x36g SATA Raptors + 2x120g WD- SE on my XP 2.6 P4. It rocks.
You mean you don't back up your porn to your $5,000 autoloading Exabyte SCSI tape drive?
Uh, actually I wasn't.
I don't know if the problem is with the modern day 3.5" drives then, but that scenario in my previous post has actually happened to me on many occasions.
BOO! TERRO
If your house blows up, the least of your worries is that you've lost your pr0n and your 1337 HAX0R SCRIPTZ, in my opinion.
I've read 2x is the better speed because the laser is hotter, which gives you a better burn without compromising data integrity. Honestly though, burning quality CD's is a black art. Everyone should use whatever works best for them.
[Fuck Beta]
o0t!
1984 and 1985. Apple IIe.
Mac floppies from 1986 on.
>> "Two words: Taiyo Yuden"
I've bought nothing but Taiyo Yuden discs for the past 2 years, and have the learned the hard way that they aren't any better. Many discs that I've burned over the past 2 years have become unreadable in as little as 6 months. These discs were stored in jewel cases, in a drawer, and handled carefully (not used as a frisbee or coaster).
I've even tried burning at lower speeds, (i.e., burning at 16x even though the discs are supposed to support 32 or 48x) thinking that maybe this would give better stability, but no such luck.
The cost of CR-Rs has dropped enormously over the past couple of years, to the point where even "premium" brands like Taiyo Yuden can be had for 30 cents (or less). And now we see why -- just like hard drives, the decrease in price is more the result of a reduction in quality than an increase in technology.
I have much more confidence in my CD-Rs that were recorded on archival quality media.
Mea navis aericumbens anguillis abundat
That's just what we tell the RIAA, that the marker preserves the longevity of our copy-protected CDs.
You get what you pay for.
I agree. Mitsui Gold and Kodak Gold Ultima (if you can find them) are the best.
Mitsui claims 100 year media life, but even 20 will be enough to last until something better comes along (holograpic storage or something equally far out).
'Your brain is God.' -- Dr. Timothy Leary
The point of the research was to measure the degradation of CD-Rs. Your CDs still work because of error correction, it doesn't mean they haven't suffered any damage over time.
...audio cds that I listen to in my car are damages within 1 month or so
That, my friend, may be due to:
1) the poor quality of the car CD mechanism when pulling/releasing the CD, scraping both sides in the process (not to forget the scraping while pushing into the CD-wallet often with one hand while trying to keep eyes on the road)
2) depending on where you live, wide temperature fluctuations will have a dramatic impact on the data surface. On sunny days, you'll easily have 30+ degC temps for prolonged periods.
The above will even destroy store-bought CDs rather quickly. For roadtrips, I now only use the cheapest CD-Rs possible and am ready to remake them once they go bad after a few months (!).
Haven't you ever heard of DDoS? SCO can't change the laws of TCP/IP, anymore than it can change the laws of economics, or of physics.
>> you get what you pay for.
This is bullshit. You don't get what you pay for.
Don't be naive.
Although they are of a similar tech, what about DVD recordable disks? I've got plenty of those now...
This would be as good a place as any to mention TDK's Armor Plated DVD Media, which are supposed to keep on working even after having been scoured with steel wool pads. Also, Verbatim makes a line of scratch-resistant CD-R media.
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
http://www.cdrfaq.org/faq07.html#S7-5
Subject: [7-5] How long do CD-Rs and CD-RWs last?
(2002/11/13)
There doesn't seem to be a clear answer for CD-RW. The rest of this section applies to CD-R.
The manufacturers claim 75 years (cyanine dye, used in "green" discs), 100 years (phthalocyanine dye, used in "gold" discs), or even 200 years ("advanced" phthalocyanine dye, used in "platinum" discs) once the disc has been written. The shelf life of an unrecorded disc has been estimated at between 5 and 10 years. There is no standard agreed-upon way to test discs for lifetime viability. Accelerated aging tests have been done, but they may not provide a meaningful analogue to real-world aging.
Exposing the disc to excessive heat, humidity, or to direct sunlight will greatly reduce the lifetime. In general, CD-Rs are far less tolerant of environmental conditions than pressed CDs, and should be treated with greater care. The easiest way to make a CD-R unusable is to scratch the top surface. Find a CD-R you don't want anymore, and try to scratch the top (label side) with your fingernail, a ballpoint pen, a paper clip, and anything else you have handy. The results may surprise you.
Keep them in a cool, dark, dry place, and they will probably live longer than you do (emphasis on "probably"). Some newsgroup reports have complained of discs becoming unreadable in as little as three years, but without knowing how the discs were handled and stored such anecdotes are useless. Try to keep a little perspective on the situation: a disc that degrades very little over 100 years is useless if it can't be read in your CD-ROM drive today.
One user reported that very inexpensive CD-Rs deteriorated in a mere six weeks, despite careful storage. Some discs are better than others.
By some estimates, pressed CD-ROMs may only last for 10 to 25 years, because the aluminum reflective layer starts to corrode after a while.
One user was told by Blaupunkt that CD-R discs shouldn't be left in car CD players, because if it gets too hot in the car the CD-R will emit a gas that can blind the laser optics. However, CD-Rs are constructed much the same way and with mostly the same materials as pressed CDs, and the temperatures required to cause such an emission from the materials that are exposed would melt much of the car's interior. The dye layer is sealed into the disc, and should not present any danger to drive optics even if overheated. Even so, leaving a CD-R in a hot car isn't good for the disc, and will probably shorten its effective life.
See also http://www.cd-info.com/CDIC/Technology/CD-R/Media/ Longevity.html, especially http://www.cd-info.com/CDIC/Industry/news/media-ch ronology.html about some inaccurate reporting in the news media.
See "Do gold CD-R discs have better longevity than green discs?" on http://www.mscience.com/faq53.html.
http://www.cdpage.com/dstuff/BobDana296.html has a very readable description of CD-R media error testing that leaves you with a numb sense of amazement that CD-Rs work at all. It also explains the errors that come out of MSCDEX and what the dreaded E32 error means to a CD stamper. Highly recommended.
Kodak has some interesting information about their "Ultima" media. See http://www.kodak.com/global/en/service/cdrMedia/in dex.jhtml, specifically the "KODAK Ultima Lifetime Discussion" and "KODAK Ultima Lifetime Calculation" white papers (currently in PDF format). The last page discusses the Arrhenius equation, which is used in chemistry to calculate the effect of temperature on reaction rates. The Kodak page defines it as:
t = A * exp(E/kT)
where 'exp()' indicates exponentiation. 't' is disc lifetime, 'A' is a time constant, 'E' is activation energy, 'k' is Boltzmann's constant, and 'T' is absolute temperature. The equation allows lifetime determined at one temperature to be used to establish the lifetime at another. If a disc breaks down in three mont
If any of you DDoSers read this: GODDAMN IDIOTS!! FUCKING MORONS! STOP IT!
I'll tell you what's wrong with my homepage (http://www.geocities.com/SCO) : IBM set it all up !!!
IP law confuses me. I am persuaded slashdot readers who read this sig now legally owe me 699$
...I back up all my data to stone tablet, granted, the seek and write times are abysmal, but they will last for centuries.
;o)
If it was good enough for the ten commandments, it's good enough for my pr0...ahem...work backups
I am NaN
haha nice. You can see how many floppy disks are necessary to store the data of 1 CDROM IN THIS PICTURE
tar -czvf asian\ lezbos\ HOT\ HOT\ HOT.avi docs/
put that in your shared file. Bam, distributed backup.
Sadly, it seems there are some cross-compatibility issues with floppy drives or the floppies themselves nowadays. I can write a floppy on one machine, go to the next machine and have read errors. The floppy is still quite readable in the original machine.
This was really annoying when I was trying to make a boot disk for the second machine. I guess the fact that it finally worked after trying several floppies might suggest shoddy floppy material, but why were they error free on the first one - a mystery to me...
Good idea. Not being a chemical expert, I visited an industry leader to gain a chemical enginnering degree and learn about the latest in organic dye technology. E2 taught me Quantum mechanics so another prevention method is now obvious.
Take a burned disk and a blank one and rub the 2 together. Rub vigerously, we need to entagle a good number of them 'purty quantums. Now re-burn the same stuff onto the blank disc as the written one. Easy eh?
Try to ensure you use the same image and burner otherwise you'll get a ghosting effect of the data and you'll have to re-orientate your antenna.
If I understand correctly, that film is made for the data side. I was meaning the label side, since there's no coating on that side and scratching it would be much worse than scratching the data side.
I also suppose that this makes the CD more vulnerable to chemicals and degradation, so the idea was to cover it with something to see if it helps.
if this is true then I wont be able to play my Napster files,
they make it so hard for people to copy things now adays.
what next, my XP ISOs wont install?
CDRs are much more reliable than hard drives. Each hard drive has a high probability of failing in the first two years. That's likely why the warranty on new drives was recently reduced to 12 months. CDRs, if they are high quality and are properly stored, can last many years.
But when it comes right down to it, how do you know it isn't your $19 CD-ROM drive you're using to try to read it? Or perhaps the OS just simply not agreeing it? Every time a disk is "unreadable" in my Plextor Ultraplex, for some reason it is perfectly fine in another PC containing an old-school 12x drive, therefore it's not "unreadable".
I need to take a huge dump, hold on, I'll be right back.
Hmm? I feel so ripped off!
they've probably been testing flying cars for the last 100 years too!
It is an internet based backup service. I guess aimed at business. I don't know what the cost is, but if you have very important stuff, it might be the thing to use.
"Whenever I think of Linus, I ejaculate." - all communist hippie linux users
p.s. - SCO called, they want their code back!
This Site has been kicked around slashdot lots of times and depicts a man, a dremel, a CD and 30,000 RPM's of angular velocity.
[Fuck Beta]
o0t!
My 5 1/4" floopies, for my beeb,
are nearly 20 years old, and still
working...
They sure don't make 'em like they used to.
The floppy disk is dying!
>1984 and 1985. Apple IIe.
>
>Mac floppies from 1986 on.
>
>
Atari 800/800XL cassets and 5-1/4 floppies
I'd rather buy a proper IDE RAID (not some software based HighPoint-RAID you find on mobos these days) for $300, 8 drives (4 active, 4 hot spares). That's about 160 GB fully redundant drive space for you for $1000.
From a backup perspective, the keyword is not only redundant data-storage - but also removable data-storage. Which hdd's lack. What to do if the server building burns down and your hdd's is no longer to use?
+Funny, yes. But it might actually work when you embed the data into real pictures/movies. The technique of embedding is known as "steganography", and sometimes also as "digital watermark".
.WAV files. You could choose to use only the lower 4 bits (WAV 4x as large as hidden data) or the lower 8 bits (WAV 2x as large as data).
Scramdisk was an open source program to create encrypted containers (mount as driveletter in windows) in
Be the first to post a FLAC (lossles audio compressor) of the next hot EMINEM album, with some 200 MB of your personal encrypted backup hidden in it, and your backup will live forever!
Marc
One idea is to store the MD5 sums of all data files somewhere, possibly on the CD itself. Then you can know if the files On CD have been corrupted.
This is the best MD 5 calculator I've found for Windows: MD5sums 1.1. It's very fast and also does batch command-line calculations.
Maybe a better idea is to store all data meant to be written to CD in Zip files. Archive files have a CRC stored for every file. The unarchiving software will complain if the CRC does not match the file.
However, the CRC in a zip file is only 32 bits. I put 2**32 into Google and Google Calculator answered: 2 ** 32 = 4 294 967 296. So there is one chance in 4 billion that a file is different but a CRC is the same.
MD5s are far more unlikely to be identical if the files are different. I put 32 ** 16 into Google and it answered: 32 ** 16 = 1.20892582 x 10**24. Them is good odds. (There are 32 hexadecimal digits in an MD5.)
WinZip 9 beta has a command-line option to encrypt with AES. Encryption acts as a checksum that can be even more secure than an MD5.
Unfortunately, the design of archiving software like WinZip is still primitive. Archiving software should be able to prepare archive files of a given size, and span to a new archive file when adding another folder (or, optionally, a file) would make an archive too large. Then you would be able to retrieve the files easily, since each CD would have a complete archive stored on it. At present the spanning option of archiving software is stupid; it is necessary to put all the spanned archive files back together to retrieve any information.
Rather than snippets, here is a reliable translation of the entire article.
"
CD - R garbage (September issue)
Tuesday 19 August 2003
CD-R unreadable within two years
Random sampling provides worrying results
Jeroen Horlings
Imprtant data on a cd-r are in practice not always easy to keep. From our practical test, published in the September issue of PC-Active, it appears that data on a cd-r may become unreadable within two years. It is very likely that by using certain cd-r brands important personal information may be lost.
As you probably know, as a reader of PC-active, we tested quite a few cd-r in 2001 and we then published the results. It appeared then that new cd-r sometimes did not conform to standard quality requirements. We kept the thirty different branded cd-r which we tested in a locked cupboard. Before this article we tested these cd-r again with a professional cd-r analyser which watches to an extreme precision what is the current condition of the cd-r.
On this image you see exactly the same cd-r. On the left you see the result of the test in 2001, on the right the same cd-r in 2003. Colors express the seriousness of the error in the order of white, green, yellow and red. This represents easily readable (white) and unreadable (red).
From the test it appears that a number of cd-r had become completely unreadable and that with other cd-r the data had become partially unreadable. Data which had been put onto the cd-r twenty months ago had become unreadable. These were c-dr of both known and less known manufacturers.
It is assumed in general that cd-r at least remain usable for ten years. Some manufacturers claim even a usability of a century. From our sample testing it seems that there is lot of garbage on the market. We have found cd-r which should have never been placed on the market. These came possibly from unreliable suppliers. It is unacceptable that cd-r content has become, within about two years, totally unusable.
In the September issue of PC-Active, available on 22 August, the shocking results are described in detail. Besides the possible reasons for the data loss with passing of time we provide also a number of useful recommendations to preserve data on a writable cd. On the free cd-rom there is also a program allowing to assess the status of a cd-r.
[ i ] PC-Active September 2003
(available from 22 August)
EUR 6,99 (including free cd-rom)"
I am afraid I don't find this exactly mind-boggling. Perhaps over here in Europe we are more critical of stupid manufacturers' claims...
Thufir Hawat
Part-time Mentat
Why does the source of the data matter, as long as it is not corrupted?
For $5000 you can get an LTO tape drive and get 100/200 GB tapes. Basically your hard drive setup i equal to two tapes. Also shipping RAID HD's off to off site storage is a lot harder than with tape. Finally anybody who argues that RAID is a substitute for tape back up has got no idea what he is talking about.
I just have four drives. 3 of the which I switch between regularly. Mostly I only change one drive once a week. This way I have a two week old backup ready. Just buy some more drives if needed :)
So true. Most "high quality" brands have relatively cheaper models named "professional", "budget" and the like. They are manufactured by the same factories who produce the $0.2 media (CMC, Princo etc).
Donate free food to the hungry at The Hunger site.
Do a full backup once a year and a 20 month lifespan for the media doesn't matter...
Personally? I get my insurance check, pay off the house, and either move or rebuild. Then I buy a new computer and start again.
IOW, the most important stuff on my hard drive is backed up off site (At work) and it's a pretty small amount of stuff. Everything else is games that I can replace after I take care of the important part, the house.
Pulp Audio Weekly - Geek News and Reviews
Most writers today do not support 1x recording. Mine, for example, start from 40x.
Toasties!
"Darn, my winmodem won't work with Linux? I'll have to recompile it... with my blowtorch."
Ahhh, any veteran of the Commodore 1541 floppy drive can tell you what this is: alignment errors. You see, the head is moved using these little step-motors. With use, the motors drift out of alignment, meaning the head moves somewhat less (or more) per "kick" than it's supposed to. As long as it's the same motor, that error occurs on every operation, so there's no net effect. (That is, sure, the data's in the wrong place. But during read-out, the head will seek to the (same) wrong place. So no error.) But move that disk to another machine, whose step-motor has a different alignment, and BAM! read errors.
Fans of the C1541 will remember what happens when that drive found an alignment error: CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLAC
The Mongrel Dogs Who Teach
It's called WinRar. Make your archive (don't choose to create a solid archive) and you can take out any file you like that isn't 'broken' by your spanning (and winrar lets you know which files those are in the archive). So no, the spanning options of archiving software aren't stupid, you've just been using the wrong software.
[Fuck Beta]
o0t!
Now, I have an answer when my firends keep asking why I am *wasting* money backing up to Jaz disks when I could be using $0.14 cdr disks. Hahaha and They called me MAD.
Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
a quite complete site is found here: www.cdmediaworld.com .
oh. and my 2 : if you intend to use cds for backup, except using the good kind, also make sure you are not writing or sticking labels on the cds, keep them in plastic covers intended for storage (not crystal boxes, since they give off fumes that damage the cd), and keep them in the dark with some moisture absorbing stuff alongside.
f64 : tutti bianco!
Oops, that would be 4x.
You should have taken up drinking. That would have filled that void you had when you stopped going to church.
It could be argued that the manufacturer owes you at least a refund, if a CD-R loses its data in only a few years (although the equipment and method of burning also play a role, over which the manufacturer has no control). Years ago, I used to buy 3M diskettes because it said "lifetime guarantee" on the box. When I went back to the shop with a bad one, I had to convince the guy to replace it. "That just happens sometimes" he said. Anyway, replacing the defective media is about as much as you can expect. However, due to the abysmal results in the PC Active test of the CD-R's sold by the Dutch drugstore chain Kruidvat, they now offer to attempt recovering the data if you have one gone bad. See: article (in Dutch). Apart from the Kruidvat brand, Platinum and MMore are specifically disappointing: article (Sorry, also in Dutch)
Read the fine article. Only SOME CD-Rs are affected by this. Basically, all of those that you can get for a 5 cents per disc are absolutely worth what you're paying for them. Diddly and squat.
If you buy a name brand, like Verbatim or Memorex, you should be okay.
GJC
Gregory Casamento
## Chief Maintainer for GNUstep
It seems that a lot of people are having this "lucky" streak. I attribute it to discrepancy between the quality returned from the reviewer's software and the actual quality your burner needs to read the CD. You notice how they said the CD's may be completely unreadable, but they didn't say that they actually tried to read them! I'm thinking they are underestimating CD-R/RW's reading abilities. Heck I've had problems with driver CD's that are unreadable right out of the box in my DVD-ROM drive. I throw it in my CD-R/RW, make a copy and the DVD-ROM reads the copy just fine...
I usually do a sort of incremental backup of my files. Now I would have to go through all of them and re-back them up.
On the other hand, the RIAA must be smiling. Here goes my backed up mp3 collection.
The fact that it's Windows only would be the least of your worries. If CDR is an unstable medium, how much more unstable is paper? It rips, it burns, it turns yellow with age, you spill coffee over it... My war3z and pr0n is staying on the mirrored IDE raid until the next disk upgrade.
It's that one CD that has the problem that will contain the documents proving that you wrote the original source code that SCO is now claiming.
-- Drug prohibition laws help fund terrorism.
We must be alert to the danger that public policy could become captive to a scientific-technological elite. - Eisenhower
Padus DiscJuggler will verify the contents of most disc images (.CDI, .BIN/CUE, ISO) after burning, even if you write in RAW mode.
I don't know if it verifies normal filesystem-to-ISO burning, because I use Nero for that.
Back when cd-r's cost me $10 a piece--anyway, I still have a cd from about 6 years ago and I can read it fine. They were gold colored on top and deeep green on the bottom.
OK, people have posted translations of the linked-to abstract a bazillion times by now, but what about the article from the paper mag?
Any Dutch readers who'd care to post at least the test results + brands?
Help savingAmigaOS and a free PowerPC market
I have CDRs that are 5 years or older and still readable. The ones that have lasted the longer are the ones I kept in a cold, dark place. The ones I left in paper sleeves or Case Logic binders looked like crap within weeks.
I also have retail CDs that are less than 5 years old and have CD rot, so don't think you are safe just because the CD was pressed instead of burned.
Pedro
----
The Insomniac Coder
p.s. - SCO called, they want their code back!
here it is:
Check out this article on CD-R quality done in 1999.
To sum up the article, price is directly proportional to quality. The company that has the most quality CD-Rs is not surprisingly Taiyo Yuden...the creator of the CD-R dye process.
The overall finding is that the cheapest CD-Rs suck. Pretty much anything made by Ritek, CMC, or Princo will suck. This does wipe out ~90% of all CD-Rs out there. Imation, Memorex, and all of the silver CD-Rs are made by these cheaper companies.
Some of this information is dated, but I have found that Fuji CD-Rs in the blue spindles are now the best source in the states for CD-Rs by Taiyo Yuden. The article I linked to states that Fujis are made by Ritek. This is wrong. I am reading one of the Fuji CD-Rs right now that's over 3 years old and there's not one error.
I suspect that CD drives also have this capability, just that software doesn't bother to use that info. Actually, most software doesn't even appear to check for non-recoverable errors so I suppose it's being consistent.
The drives we use to backup our systems write at a sustained rate of 30-40Mb/second each. The fast drives are expensive though.
Government of the people, by corporate executives, for corporate profits.
And what kind of dye did the CDs use?
I remember when I was first investigating what brand of CD-Rs to buy. I read an article on the differences between the dyes used in CD-Rs.
Don't remember the exact details, but it was something along the lines of the chemical combination used to make CD-Rs with green dye are better for single speed reading (eg. Audio CDs) but didn't last as long. The chemicals used to make the silver/gold dye however were superior for data, and should last somewhere in the order of 20 years. I think blue dye was somewhere in between.
This similar article says gold dye CD-Rs have 100 year durability, and the cheaper green ones only have a 10 year life, but have been enhanced to give 20-50 years of service.
So the discs are readable, in that one could make a complete and perfect bit-for-bit copy? The issue is that the error-correction is being used after all that time?
You can't judge a book by the way it wears its hair.
Stick a cd-r against your monitor, if you can see through it, you're out of luck. If you can't see through it, it's good. (Disclaimer: this may not be true)
I agree. I recall a period of time when Dyson, the most expensive floppy disks, were terrible. People who expect they are buying quality when they pay more are just paying more. Unfortunately it takes research and trial and error to get quality, and even then the manufacturer can switch how they make discs (or anything else) at any time.
Okay, I'll try WinRar. However, I would like an option not to break any file.
According to this CD-Recordable FAQ entry , "it depends".
Fuck the system? Nah, you might catch something.
CD-Rs are too low capacity anyway. I have lots of data that I want to keep. I have a 120GB USB2 disk (480Mbps) - I use a sync program to duplicate the data. If I want historical data I zip/tar.gz or whatever is easiest for the task.
I back up my documents, digital photos, databases and web sites. And of course my code.
The harddisk in the USB2 box is easily replaced if you want more capacity!
I'm thinking about buying a DVD writer at the moment, but that won't keep me from doing my harddisk backups like I usually do.
Any technology distinguishable from magic, is insufficiently advanced.
Real men use 3.5" floppy disks for backups.
I used to work in a CD factory (from 1986 to 1994), and this is plain not true. A pressed CD consists of:
disc label
protective coating (laquer)
Aluminum layer (sputtered on)
data layer (pressed into the next layer when injection molded)
polycarbonate injection molded disc
To vary from this is a violation of the Phillips spec, and you are not allowed to put the Compact Disc logo on the resulting product.
What you probably noticed was the laquer layer was thick when we started making discs, but over the years laquer has improved to the point that only a very thin layer is needed.
If you leave out the laquer entirely, the aluminum oxidates rapidly, rendering the disc useless.
No, it grew hair ...
If you store you valuable data (most especially pr0n) for the long term, and don't have bottom less pockets, Magneto Optical (MO) is the way to go.
Fujistu is the only company I know to make 3.5 in drives in the US. About $350 for a UW SCSI, cheaper for IDE/Firewire/USB. Olympus, and Sony also sell them in Japan. Maximum Capacity about 2.3 Gigibytes around $10 for the disks (Cheaper for lower capacity).
More companies make 5.25 in ones that can hold up to 9.1 gigabytes, but the drives will cost you about $1000, and the disks about 50 a piece.
Much more convinient and eco friendly than CD-Rs, more reliable, tougher, &c &c.
For the Snark WAS a bojum, you see.
I've got 3 drives in sliders and I use a 4 week cycle for backup jobs (Monday1, Monday2...Monday4 etc). I change the drives once a week so when the drive goes back in it's getting files for a different number backup job written to it. It takes 12 weeks for the cycle to start repeating itself and the backup files to start being overwritten.
You're using her as bait, Master!
Do you remember science class where they told you a measurement wasn't correct unless it included a +/- error estimate?
Every CD burner (like every real-world device) has a certain amount of error. The device decides to turn the laser on or off, and there is a delay before the laser turns on or off. This small delay varies with heat and other factors within the device and varies with the component tolerances from device to device.
This error rate is over time, not distance. So, if the CD is rotating slower, it doesn't move as far during the error period. This results in a burn which is closer to perfect, that is it has less error distance than a higher speed burn.
Then there is the completeness of the burn; with a brand new good quality drive it shouldn't matter, but how many of you have a brand new plextor?
And of course there's also the CD media. If you bought the 10 cent bulk discs and expected them to last, shame on you. I record at slow speed to the old dark-blue verbatims whenever I can, and after 7 years I havn't lost data yet.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Did you ever look into CD-RWs?
They are a phase-change medium, either the substrate is crystalline or it is amorphous. Thats not something that's likely to change with time or degrade like an organic dye.
Starman97@Gmail.com (bring it on spammers)
The oldest CDR I've ever used must have been burned in 1994. The disc itself said it was rated for 2x burning, and I *think* the brand was Pinnacle. I saw an ad for the same kind of CDR (and a burner) in a 1994 Macworld. I think it's the burner mentioned in this article. The CD read just fine in my 24x Yamaha drive in 2000. So if all of the CD's I burn today last 6-8 years, I'll be OK, because I'll be able to transfer them all to a 1TB iPod :)
And how do you handle offsite backups for disaster recovery should your site be flooded, burnt down or subject to a week long power outage?
Disk backups are for small fry.
Government of the people, by corporate executives, for corporate profits.
Where are you getting your hard drives? I pay about $.20 per high quality Tayo Yuden disk. That's $.30 a gig. Where can you buy hard drives for the same price? Plus I can back up file by file, rather than saving my whole filesystem which is a lot more convenient for retrieval purposes. I started burning in about 2001 and I haven't seen anything fail yet. Maybe I'm just lucky.
Give me Classic Slashdot or give me death!
Is it just me, or does this floopies/beeb thing sound distinctly pornographic?
experimental audiovideo minimalism: Rebuild All Your Ruins
Remember, don't leave your CDs in the car for more than about a fortnight, or they will metamorphose into 'Best of Queen' albums.
Why does every porn joke get instantly rated "5, Funny"?
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Which of the thirty brands that failed do you recomend? I've got 20 year old casset tapes that still work because I spent a little extra money on them. The problem is that the labeling then was much more informative than it is now. The maker published graphs to match their made up words. They talked about the specifics of their technolgy and what made it better and they made real garuntees of quality. CD lables suck and no one seems to know if any is better than another.
Keep upgrading your Harddisk from time to time and backup data from old HD to new one.
This is inadequate now. With even modest cameras with tiny movies able to fill up 64M of compact flash in a weekend, your digital archive is sure to grow faster than you think it will. It certianly much bigger than CDR can hold. I filled up two CD's worth of baby pictures in my baby's first year, and we had a crappy camera for half of that. Right now, I've got about 5 gigs of photo archives. That's managable and it's easy enough for me to keep multiple live coppies going. It won't be adequate for long, however. It's been growing exponetially as my camera equipment impoves and as my friends start getting reasonable cameras. I can see that I won't be able to keep up with things.
People crippled with Windoze junk must already find it impossible. What would I do without find , tar and symlinks? I'd lose dates, file structures, and any semplence of order. If I had to rely on Windoze crummy networking and tools, it would be very difficult to look at things and impossible to keep multiple live coppies.
That my CD archives are going to fail me is greatly distrubing. I've got more than pictures, but I've only been making CDs for two or three years. I was told and THOUGHT that the data would last longer than this. I had dreams that my digital coppies would outlast the sorry organic dyes of my shoebox photo collection. Hmph.
Friends don't help friends install M$ junk.
But which CD-R's are to be trusted? The article implies that even major brands had problems. My 6-cents-per-disc CD-R's are branded with names like TDK, FujiFilm, Kodak, and AT&T. What brand can I trust, if not these?
:-(
Maybe it's time to go back to tape
it's = "it is"; its = possessive. E.g., it's flapping its wings.
Don't be a jerk. Of course there will always be people who will sell you expensive junk, but as a general rule, if you pay more you get more. The point that you could have made is that you need to do a little research before you buy, so you weed out the expensive crap from the best of breed.
I have CD-Rs from 3-4 years ago that are just fine too. Granted they are 95% music CDs so errors will be a bit more hidden.
The only time I have lost a CD-R is when I've put a scratch through the foil on the data side because of careless handling. So far, in all cases those were just copies of my music CDs (and the prime reason I copy many of my favorite CDs), so all I had to do was fish out the original and burn another copy.
I just tested a couple of CD-Rs burned back in 1998 from Traxdata, stored in a CD case which where stored in a cardboard box. ;)
And they worked fine. All that old porn.. err important business backups still worked.
I don't know what CD-Rs that duch site tested, but there are manufactures out that claim their CD-Rs are lasting centurys..
Well...the data side IS the label side. The data is underneath the paint/label.
1980 ORIGINAL DOS 3.3 system master and basics (boots DOS 3.1/3.2 disks on a 16-sector (DOS 3.3/Pascal/ProDOS) system) disks in PERFECT CONDITION (well, the labels are yellowing a bit, but other than that...). BEAT THAT! (BTW, (SS/DS)SD 5.25" disks can supposedly last 90 years if kept like a mushroom, except for the occasional read every year (every sector - that part is quite important)
...that stated the expected shelf life is 2-years for a CDR. While many can last much longer, you should not expect a realiable backup to persist beyond 2-years. In same cases, it can even be shorter, much shorter.
Wish I could remember where I read that..nonetheless, I've always told my clients to expect no more than 2-years out of the CDRs.
I had a maxell cdrom with a gash on the top of the disk. This rendered the disk unreadable. I simple
too a sticker and slapped it on like a bandaid,
problem solved!
I burn thousands of silver CDRs every year, always the cheapest possible ones in bulk, for a publisher that publishes books with accompanying CDRs.
In the last five years of doing this, we've only had problems with mold that could be wiped off restoring their usefulness without returning them to us.
Perhaps the Danish market got ripped off. It's quite possible that somebody made some money moving defective discs.
We've seen a few stacks where individual discs intermittently would fail to write a few years back. That was a hassle, but after a few months of going back and forth with the supplier the quality seemed to improve and never went bad again. This definitely sounds like there was a bad shipment.
But that ol' get what you pay for wheeze is obviously somebody's idea of a joke. Probably someone with a lousy sense of humor drinking cheap booze. You know, listening to Rush Limbaugh on AM and slurring out Ditto Rush! Every now and then.
I just found a stack of old el cheapo music CDRs in a translucent case sitting next to a window that had been overlooked for several years. I thought for sure it was all but destroyed and, indeed, the label sides were faded. Surprisingly, none of the data seemed to have any errors.
Removable hard drives. Slide in slide out. Probably best not to do it too often, but as a backup, and lock away somewhere once in a while they work.
Actually I think tape drives can be quite a bit faster then ide drives for back up.. (can be)
This is because IDE drives are made for random access, speed in them limited not by the actual read/write speed, but how long it takes the head to move from one random spot on the hd to another.
Tape drives on the other hand are HORRID for random access. Twirl stop Twirl stop Twirl.. You know the drill, but for reading a continious stream of information they are unparralled, because then the speed is limited by the read/write speed of the head and not the seek time. Once you get those babies going you can have several feet per second of tape written at a go.
That's probably why they still use tapes for backups
A spare 60 gigger rackdisk will keep you satifsied for a long time...
Considering that my computer currently has two active 120GB drives, I doubt it.
Mind you, I might not need to back up the one that's full of anime, but still...
why, photoshop of course.
I call him Gentoo and Kazaa.
thank God the internet isn't a human right.
> an alignment error: CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLACK ETY-mmmm- ERR!
And then it starts playing "Bicycle Built for Two!"
Well, give it up. What brands have you used that are fine, or more importantly, what brands have failed for you? Here's my experience:
Lesson 1: Never get a CD-R w/o any printing on it. I got some (TDK, I think) that were just silver on the top, no branding or anything, and they burned just fine, but I found out later they could be scratched VERY easily. Scratched on the top, mind you. Apparently there was no protective layer over the foil, and you could just scratch it right off. I think they were meant to be printed on by some kind of CD printer.
My TDK's that I burned 2 years ago with the white surface (w/ branding) seem to be perfectly fine though. I also don't seem to have any problem with any imations that are as old.
I have one 2-year-old CD in which the foil appears to be harboring some kind of fungus. The brand is "K Hypermedia," I think I got it for free or really cheap. You probably get what you pay for. But the "fungus" is only on part of the edge, so it still plays fine. I have a handful of others of the same brand, which look okay.
disclaimer: I take semi-good to pretty-bad care of my CDs. They are routinely left out on the counter, desk, or wherever, and sometimes stacked in tall piles, when I don't feel like looking for the matching packaging.
c-hack.com |
Priorities, my man, priorities!
No way. Paper tape buddy- miles and miles of paper tape. You can put it in a fire safe, and as long as it doesn't go over 900F in there, you're set!
Gamingmuseum.com: Give your 3D accelerator a rest.
Why does every porn joke get instantly rated "5, Funny"?
I'd explain, but it takes too long given that I'm typing one-handed.
Opinions on the Twiddler2 hand-held keyboard?
According to this site that was linked to from Fujitsu's site magneto optical drives are nearly indestructable, they have a minimum life of 30 years (good enough for me) they don't lose their magentic properties until they reach 180C so you can spill as much coffee on them that you want. =P
The drives can be had for roughly $257 for internal IDE. I didn't shop around hard, but you can get a 5pack of 1.3GB disks for $95 that's about $0.014/MB, not too shabby. They also make high end solutions with 9.1GB disks but the drives are remarkably expensive. If I were more serious about doing backups, magneto optical would be the way to go.
Fear trumps hope and ignorance trumps both
Um... Wasn't the whole point of the story that this isn't necessarily the case?
As for hard drives, yes, some of the newer brands that push the boundaries do fail with amazing regularity. However, if you stick to tried and tested kit, that doesn't push all the boundaries and puts reliability ahead of that extra 10GB per platter, then problems are still relatively rare.
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
These guys used CD analyzer hardware (CDA-3000) to check the quality of the discs.
Why is it that standard CD-ROM hardware will not allow us to do this? Providing the raw data from the media including ECC would allow some amount of quality analysis in software, and it would also help in recovering parially damaged discs. And BTW keep in mind, that a CDROM is more reliable than a CDDA, because on CDDA only 25% of the disc is used for ECC while on a CDROM 35% is used for ECC.
Do you care about the security of your wireless mouse?
According to an article on cdfreaks.com, a test done by the Dutch PC-Active magazine showed that among 30 different CD-R brands tested, a lot of them were already unreadable after twenty months
That is, of course, 2-year-old CR-R technology they tested. Have they improved them at all?
Yes, but the original poster is also corerct, floppies bought today are total crap compared to years ago. Every floppy disk I've bought in the last few years have all been unreliable at best, but floppies I bought 10 years old still work perfectly.
What do you do about the files you accidentally deleted? RAID won't help you. That's why the enterprise still uses a proper backup solution. Most of the time I'm restoring files because someone overwrote or deleted them- not because of system failure.
Gamingmuseum.com: Give your 3D accelerator a rest.
True story:
I had a 1541 that wouldn't stay aligned for more than a couple of hours. One day, I smacked the drive in pure frustration while it was gronking away - and the sonofabitch loaded.
From that time forward, SOP for loading any C=64 program was:
1) load *,8,1 [enter]
2) watch drive light come on
3) swat drive
4) PROFIT!!!!
DG
Want to learn about race cars? Read my Book
To vary from this is a violation of the Phillips spec, and you are not allowed to put the Compact Disc logo on the resulting product.
What you probably noticed was the laquer layer was thick when we started making discs, but over the years laquer has improved to the point that only a very thin layer is needed.
If you leave out the laquer entirely, the aluminum oxidates rapidly, rendering the disc useless.
I have seen this. I have a music CD that has visible "pits" in the aluminum from oxidation. There does not appear to much (read any) protective layer on that CD at all. It's unplayable now. Disappointing as I liked that band.
I have to wonder if the data CD's I've had go bad suffer from the same defect. Their results of having dead CD's at less than 2 years mimic my own experiences. I have some that have lasted 5-7 years, and probably 30 out of 300 that have died in 2 or less - plus another 15 or so coasters from bad burns. Even discarding the coasters from bad burns that's a 10% failure rate. It's not god awful, but it's enough that I don't trust it to last.
Freedom is merely privilege extended unless enjoyed by one and all.
Do you think they sit around for a few thousand years to measure the half lives of radioactive elements too?
-
Don't worry there's this program Kazaa you can use as a distributed network backup system.
Give me Classic Slashdot or give me death!
or, name the file "jennfier lopez nude" and put it on several filesharing networks, prestro! problem solved.
Are you a VF grad? Check out the VFMA Alumni Forums VFMA Alumni Forum
I'm pressing all my data backups on vinyl.
Cryogenics. Take your CD, and freeze it in a largish vat of liquid nitrogen or some better coldish susbstance. Then wait until technology improves for bringing your CD back to life - you'll have your data back!
Respected german magazine c't once wrote, that you would be able to find (corrected) errors on a CD-R as soon as you take it out of the box. After all its a somewhat delicate media, and the pure fact that a correctable error occurs is not something to worry about.
While it's true that a lot of harddrives fail within the first two years, it is very unlikely that the same harddives would fail while stored on the same shelf as you backup cd's. It's the wear and tear while the disk is in use that causes it to fail.
What if the burner has a laser that's slightly out of whack or something. At first you might be able to read it because of error correction, but it's really much worse off than those written by a good burner.
Give me Classic Slashdot or give me death!
Eh, 160GB takes about 40 days to fill up at average 50kB/s, 20 days at 100kB. Fully achievable with torrent/donkey whateva.
This might sound stupid. But what if I sealed the disc with grease, will this protect the media from reacting with atmospheric oxygen.
Later on if I want to remove the grease, which chemicals should I use so I don't damage the disc.
This poses a GREAT problem for those who trade bootlegged concert music on CDR. To a lot of traders it is out of the question to Exact Audio Copy their collection over and over for time/money/quality of extraction reasons every few years. Some refuse to even write on CDRs with sharpies fearing the ink may seep in and damage the recording over time.
Are printers and scanners good enough to make it worthwhile? I don't know. I haven't run any tests and I don't even have a good feel for how many bits you can print on a square millimetre of paper and scan back reliably.
But let's pretend we can print and resolve three pixels per millimetre and 3 levels each of cyan, magenta, and yellow per pixel, and that we're using A4 paper with 10mm margins.
bash> bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY. For details type `warranty'.
ppmm=3
bpc=3
bpp=3*bpc
margin=10
width=210-margin*2
height=297-margin*2
bytes_per_page=width * height * ppmm^2 * bpp / 8
bytes_per_page
532878
bytes_per_page/1024
520
Damn, just 520k for a whole lot of trouble, paper, and ink.
But, as I say, I don't have a good feel for what bpmm and bpp really are. Does anyone know? Has anyone heard of any attempts to actually do something like this?
Fuck the system? Nah, you might catch something.
Burn them in lover speeds. 2 years durability thats what you get when you pay a lot of bucks so that insted of waiting 15 minutes, you only wait 10 minutes.
And then there is all the windows lamers who dont understand that windows cant multitask, and that multitask doesnt mean what bill gates says it means, so they sit and do a lot of shit stuff with their computers while burning that cd for five minutes. Then they wonder why it doesnt work, why the cds doesnt last or why some computers cant read them.
With the costs of hard drives dropping rapidly, one can pick up a 200Gb hard drive for under $300. Why not just pick up a spare hard drive thats used for backup only purposes... 200Gb is more then enough room for all your pr0n, MP3's, DIVX, and of course legit documents
this study has been using media that were made at least two years ago. Has CD/R technology made any leaps recently? Maybe new manufacturing or CD burning methods result in better (and longer) burns.
It's not only the disks. Try a disk in a drive made pre-1995 (1991-92 is the best). Works pretty well, doesn't it? Then, try it in a drive made in, say, 1999-2002 (2003 drives don't eat them yet) - ESPECIALLY in a computer that doesn't have a standard front panel on the FDD, it just uses a hole in the front panel of the entire case - like most major brands of PCs in that time. It's probably saying "Write Protect Error" when it does work, and if it's not, there'll be major data errors during the writing (and reading) process. Then, try it in the old drive again after you've spent 10 minutes trying to get the drive to recognize your disk. (ARRGH! THE NEW DRIVE ATE MY DISK!) BTW, when you decide to put the FDD from your old 486 in your 'leet Athlon XP box (or your old 466 Celery - don't lie), DON'T DROP IT! Anyone got tips on recalibrating a Teac 3.5" 1.44MB drive circa 1990 (I think that's what it needs - it was dropped and whenever I try to access it it pretends there's no disk...)?
But then there is the question what will the glue do to the data layer. The paper could also cause balance problems with high speed drives.
Begging for modpoints since '03
Long story short the rule of thumb was like this: Green CDs have a life of ~5 hours. Yellow CDs ~20 hours. The DARK DARK Blue cd's (not light blue, the only brand I know of like this is Verbatim) *600* hours.
The price increases correspondingly as well. I found the best solution was to use blue's for backups and critical things, and regular commodity cd-r's stuff for day to day things.
Religion is a gateway psychosis. -- Dave Foley
Hell, I've got 20GB just of Ogg Vorbis files ripped from just 1/2 of my CDs. I'll fill 40GB with music before I get done. And I know that ripping music is not some geek-only process.
:)
Add to that 10 or so GB of source materials for graphics and presentations, 5 or so GB of presentations and 5GB or so for a full install of 2 modern OSes and I've eaten up 60GB without trying hard.
And without pr0n for that matter
Modern backup solutions just do not cover that for a reasonable cost for home or SMB users.
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.
that's why I keep it on the HD
I wouldn't trust it considering the amount of corrupted files I get from P2P.
Begging for modpoints since '03
THAT is the disks. However, try this. Take a heavily used computer made circa 1999 and a computer made circa 1991 (hell, make it used till it bleeds - primarily the FDD, though). Throw a disk in the 1999 PC and write a file to it (ONLY FAT12 HERE, MAKE IT FAIR GAME) if you can. Throw it in the 1991 PC. Try reading it. Then read a known good disk in the 1991 PC. I rest my case. Also, try getting software duplication grade floppy disks. They're better quality. (Except when they're AOL disks, which seem to self-destruct after two or three writes.)
Kodak Gold Ultima Media FAQ
These Frequently Asked Questions (FAQs) were last updated on 5 March, 2002.
How can I custom order KODAK CD-R Gold Ultima media? With KODAK's announcement on January 24, 2002 that it is discontinuing its CD-R media products, it is no longer possible to place custom orders for Gold Ultima media.
Quality is a dying industry.
I didn't know Linus worked with the Lunix development team!
you'll know it when you'll have some hairs on you balls ;)
That article is like those tv news ads, like the one from Simpsons where Kent Brockman said: "A leading brand of cola causes cancer, but we won't tell you which one till you watch the show!"
Well, where is the list of CD-R's that will go bad? I couldnt find it on the link, anyone have a quick list?
That's what happens with my ONE WEEK old 3.5" DSHD disks. Target floppy drive that this occurs in is invariably the one that came installed in my current server (the HP). It doesn't happen in my old Toshiba laptop... OLD 3.5" DSHD DRIVES RULE! DON'T TOUCH NEW ONES!
Sorry, I can't read Dutch.
And then it starts playing "Bicycle Built for Two!"
OMG. I weep. Visibly.
Which is OK for backup, but that is not the issue at hand.
The application which will have a problem with the short life found for CD-Rs is not backup, but archival storage.
Eg, where will you store your digital photos? For that kind of ordinary, real world application we need a medium with a life measured in at least decades, preferably centuries.
_O_
.|< The named which can be named is not the true named
I had the exact same complaint about that article being a teaser.
;).
Can someone get a hold of the full article and give us a quick list of CD's to avoid? Which are the best?
Post the article to freenet if you are scared of getting busted for copyright infrindgement
Because you probably had a good quality disk. Nobody makes good disks now. (Unless they're expensive software duplication grade.) I've lost many a report due to the Fujifilm and Imation (don't even get me started on Sweatshop Diskco grade disks...) $#!7 grade disks that are out...
Macintouch had an indepth discussion of CD-R failure
This troll isn't even original, it's plagiarized from here: http://www.exchangedlife.com/article1.htm
The machine is usually a Sony CD-RW CRX145E, recording at 10X and re-writing at 4X. I have faster burners on other machines, but those are newer, so I can't yet vouch for their quality.
Interesting theory, but my 48x Lite-on drive doesn't seem to let me burn at less than 4x, under Nero or NTI software. What new equipment will still burn at 1x?
I'm an American. I love this country and the freedoms that we used to have.
Um...use a cheap opaque cd label on that side...
Here on Slashdot there are many things that divide us, emacs vs. vi, SuSE vs. Debian, the best Dr. Who, all sorts of geeky crap. There is one thing that unites us all- our love of pornography.
-Barry
given the current amount of hard disk storage, and the fact that HD prices are going down, I think that the best way to backup your sensitive data is to keep it on a separate machine, with a raid-1 (mirroring) storage system. I don't believe anybody could have more than a few gigs of relevant, personal data. if a disk fails, you get a new couple of one, change the failed one, reconstruct the mirror. Once the other has failed, you change it, reconstruct the mirror, and you have a bigger raid. You may have to work it out a little bit with LVM and other stuff but it works.
-- There are two kind of sysadmins: Paranoids and Losers. (adapted from D. Bach)
Well duh
I wouldn't. I spent some time working as an operator on mainframe sites years ago, and ran into lots of situations where data had to be salvaged from bum backup tapes. They can be a real pain in the ass.
From the link you provided:
Pinnacle Micro Systems
1000 RCD (double speed) available for under $1,100 (including software)
CD blanks cost >$25.
This price should come down further as technology develops.
I actually used one of these for my primary burner up until a couple of years ago. Caddy loading goodness. Come to think of it, the thing never burned a coaster, either.
(And it was under $1,100. I believe it was about $1,100 dollars less than that. A friend found it in a dumpster and knew I didn't have a burner.)
--saint
If the dics use an organic dye that degrades, would it not be smart to place backup discs in a vacuum-sealed bag in the freezer? Cold, dark, air tight.
You'll need more space than the source, but you can also provide a backup every hour or less if you want (you could even rerun the script as soon as it ends, providing you a shitload of incremental backups), and thus able to restore files with more precision
It's #42 in the OReilly Server Hacks book.
My porn, my precious antique porn.
Physical attrition is one thing, but they are surprisingly resistant to chemicals. If you use the proper marker pens to write on the non-shiny side, you can actually wash it off with acetone. Lots of plastics just make a messy smear with that kind of treatment.
If you can't figure out which files you want to delete, you're a doofus; go and use Windows and then you can take your poor "accidentally deleted" files right out of the recycle bin.
We used to send paper files to Kodak to be put on spools of film (sort of like a spooled microfiche). What a PITA! But fairly durable. But the machine that read the films was old, there was not a replacement, and it always seemed like it was going to break down.
It was also pretty darn expensive to get the documents imaged.
-- Hello_World.c: 17 Errors, 31 Warnings
Why is everyone surprised? The only means of data storage that has been tested to last 100+ years is to write it out to paper. For extremely critical stuff, it's typically printed in a small font on acid-free paper, then stored in a climate-controlled vault.
Paper tape is also a viable alternitive, however due to the need for flexibility in rolling the tape, it cannot be manufactured at the same strength as the rigid punch cards. Furthermore if absoultly neccicary for extreme reliability punch cards can be fasioned out of steel or other metals creating a computer media with a shelf life of thousands of years without data loss.
Little Brother, watching the watchers
I have found that only 2-3 brands(out of dozens tried) work decently on anything but the originating drive. I commonly burn "home videos" to SVCD for my DVD player, and PSX "backups", music "backups" in an OLD cdplayer, as well as a quick way to transfer files to my old 486, and the best brand for my uses is verbatim, with fujifilm coming in second. All generic brands seem to fail on at least one of the devices I use except those. Maybe it's just because my burner is japanese that is favors japanese brands, I have no clue.
True genius is grasping a situation like a peice of fruit, and peircing it just right so that it drains dry.
Windows 3.1 required. WINE can handle virtually all 16-bit code. Direct download at http://www.simtel.net/product.php?id=27742
I restore my files by reading it back from /dev/random. Takes a while, but every file i've ever had is in there.
I think your bits per color to bits per pixel is artificially high.
I would bet there is some bleeding going on. You're going to have a very highly inked up page, and the paper may not be able to reliably hold all of that ink where you want it.
Second, many non-professional quality printers do not have enough precision in the alignment of their heads. You may be able to correct for it, but its probably a whole new can of worms.
Third, you would need some CRC type error checking in your color mapping algorithm. You already need to be using the best quality paper available, and you need to never let anything touch it, but I still think there are enough defects in the paper that you need error checking.
That said, a lot of these objections don't hold up for laser printers. When all is said and done, you could probably find a way to put 10k on a page with decent reliability. 10k may not seem like a lot, but it is plenty of space for a GPG private key, maybe a biometric signature, maybe a map to the secret treasure. Then you just need to find a safe-deposit box secure enough to hold this piece of paper.
Troll Like a Champion Today
She did have the grace to blush when I showed her the offending cards and asked her how a card-reader worked :-).
Yeah, unless you need to get to something you need from over a year ago, like tax records, or an article you wrote. Files can become corrupted on the hard disk too, and you won't know it until need it. I guess then your up the creek if you don't open all your files every 20 months. Not so simple. Isn't the point of a backup so you can go back in time?
This quality issue is unbelievable. The organizations that license the logos and the technology need to up the standards and start pulling manufacturing rights if they aren't met. This is unacceptable.
OK, I don't read Dutch. But I figured I could spot brand names, I read the English "summary: and then went to the Dutch article, but I saw nothing at all giving me any idea what brands they tested, what brands were bad, and most importantly, what brands survived. Can anyone provide a link to this information?
I'm an American. I love this country and the freedoms that we used to have.
Use decent branded CDs. We all know the benefits that are given by branded over unbranded (less chance of the metal scraping off) but it also gives more reliable storage. I've got hundreds of cdrs burned over 5 or 6 years, mostly on Maxell branded 700mb cdrs - none of which have lost any data. The philips I used too have lasted just as well.
The unbranded spindle I once bought however - all of which have either scratched completely due to the metal being unprotected, or have just stopped reading.
(All were burned on either my HP USB external 12X, or my Philips 4800)
Try cgywin.
As you point out, you can avoid problems by refreshing your media when the newer larger stuff gets cheap. I have a ton of data on CD that I want to preserve, and when DVD-R gets cheap enough (around $0.50/DVD or less) then I'll start transferring it all. Data is forever, but media sure isn't.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The important thing to remember when buying CD-Rs is to examine the packaging carefully. Some Fujis (particularly the spindle packs) are manufactured by Taiyo Yuden; some are not. The manufacture should always be listed somewhere on the packaging.
Now that I'm halfway through my dwindling spindle of Mitsui Golds, I supplement with Taiyo Yuden Fujis found at Fry's Electronics. I've never had a problem with either the Mitsuis or the Fujis.
We're already at a doller a gig now, in 20 months we'll be at half a buck a gig, and in another 20, a quarter a buck a gig. And harddisks have supposedly been increasing in dependability. Plus, I know most of you have noticed motherboard manufacturers putting raid functions on their boards more and more often. You can go out, blow some money on a pair of big hardisks and raid them. 250 gig/$243= $.97 a gig 50 CDR pack * .7 gig/$20 = $.57 a gig
We have yet to see a removable storage medium that is as flexable, cheap, and portable as the CD. There's DVD-r but that only does what, 2 times that of a cd-r? I'm thinking something that holds around a half a terrabit a disk...
Candy-Coated Knowledge
Tell the drunk Indians to stop nibbling on the fiber.
Removable hard drives. Slide in slide out. Probably best not to do it too often, but as a backup, and lock away somewhere once in a while they work.
Sure, but then you have other problems:
First, unless you plan on taking the server down for every backup (that's not a serious alternative), you will need hot-swap drive bays, adding to the cost.
Second, you need at least two full sets of hard drives since you should never be overwriting your single current backup.
Third, harddrives can probably survive being swapped once a month regularly, but not once a day. That means you are *planning* to lose up to a month of work if something happens. That's not acceptable in most real-world situations (but perhaps for your pron collection).
Mylar laminated tape is even better. It lasts longer than regular paper tape. It tends to wear out punches prematurely.
Mea navis aericumbens anguillis abundat
Programming can be fun again. Film at 11.
Sorry paper rots over time, and there is always danger of a fire. The ultimate backup is cuneiform on clay tablets. They remain readable after thousands of years.
Quemadmodum gladius neminem occidit, occidentis telum est
I've always wondered if this [burning at 1x speed results in better CD's] is actually true or not.. I have yet to see any actual evidence to back up this claim...
Well, head on over to cdfreaks.com website and take a look at the results of some tests. For the lazy among us, burning at 4x resulted in more C1 errors in every test posted (on page 1, page 2 timed out) than burning at a higher speed (usually 40x, but one test was at 52x). A comment on page 2 indicated on person did 4 tests, and half said burn at high speeds and half said burn at lower speeds. Overall, the small sample of results indicated that burning at low speed usually makes things worse, not better. Surprising huh?
Ultr@VNC Viewer takes two pages (printing at 600dpi Laser quality on a 1440x720dpi Inkjet for flatbed 300 and 400dpi scanners). Doesn't seem very efficient.
plus.... Flash memory won't retain data for more than 10 years (in theory!! From experience: even worse!) ;-)
After all, it's just a few nanocoulombs of charge trapped in silicon oxyde (floating gate MOSFET). Try mask ROMs instead
I still have the two CD-Rs that were included with my first CD recorder I bought about 10 years ago. They are hp brand and were recorded 2x speed. Both are working fine.
Not that there is anything of interest on them of course. At least if you are not interested in Winzip 2.0 or something of similar age. I just keep them out of curiousity how long they will be readable.
RedShirt
Microsft spel chekar vor sail, worgs grate !!!
We've upped our standards. So up yours.
would it help to put them in the fridge like rolls of film?
I don't think this is so much a compatibility issue. I've experienced this in a computer lab of identical but sadly worn-out PCs. It appears that some of the drives are just losing it.
I just pulled out a few CD-Rs that I burnt in early 97 when I purchased my first burner (1x). Guess what? I was able to read all of em without any problems. We're talking 6 1/2 years ago. So I'm not worried.
It's better to burn out than to fade away
I remember way back when, around when CD-R's first came out, they had a type of organic dye that appeared gold whos purpose was for data archival. I have a few of these and quite a few of the old blue Verbatims and some no-name green media. All of these are still quite readable, and they were burned in 1996. Perhaps one of the reseachers in the article left their CD-R's on the dashboard of their car and didn't own up to it.
. shtml
The other thing to consider is that DVD-R/+R technology is dropping though the floor. I bought a Pioneer A05 for $320 in January and today the A06 is going for $229., and remember I bought this thing from the same place I linked to. I don't know how DVD-R is for archival, but my point is that at the rate the technology is falling in price, CD-R may not be around much longer anyway.
In any case, I found a rather excellent guide on the different tyes of CD-R media. It goes over all the dyes, their manufacturers, theoretical lifespans of the dyes, etc. I recommend a visit...
http://www.cdmediaworld.com/hardware/cdrom/cd_dye
-R
I guess just like audio and video cassettes, buying cheap is a false economy, and you want a quality brand for anything you're not going to throw away shortly afterwards. I was thinking about this just yesterday, while considering which of the vast array of CD-RW media before me to buy.
The question is, how do you tell what the quality brands are? Does buying in bulk always imply cheap and nasty, and buying a well-presented set of 10 CD-Rs with jewel cases always imply high quality? I doubt it.
I, too, have a set of the nice blue Verbatim disks, which have given me no problems thus far. I've also used the Master "Audio" 80min brand to record (legally!) music onto CDs for use at dancing events, and have had no problems with these. Both cost more than most brands on the shelf at the time I bought them.
That said, I always burn at well under the maximum quoted recording speed of my drive to reduce error. There ought to be a disclosure law on CD recorders/rewriters that using the much-advertised higher speeds will reduce the effective lifetime of the media.
Yesterday, I bought a set of 10 imation "1x-4x compatible" 650MB CD-RWs. Again, they were one of the more expensive brands on display, they're from a known brand and they look to be decent kit, but how do I tell? Certainly the label on the back of the pack -- basically a disclaimer in case you lose data because the disks are bad -- isn't very reassuring.
So, given the pool of knowledge we have here on Slashdot, perhaps this is a good place to ask: which CD media brands do you find are reliable, and which have caused bad experiences?
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
It's a shame "pen drives" and the like are still so expensive. A portable, robust hard disk that basically just sits in your pocket and plugs into a USB port when needed has a lot going for it...
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
I haven't had any high quality CDRs go bad on me yet. And by high quality I don't mean your bulk spindles, I mean Mitsui Gold, Tai Yuden, Kodak Gold (no longer produced), Verbatim DatLifePlus (stay away from ValueLifePlus), etc...
To be extra safe, I run two CD-R drives to write two copies of the data to two different brands of CDR medias at the same time. Then I also overlap the data for the next batch -- taking half the data from the previous CD, and adding new data to fill the new one. So that any given data is on no fewer than 4 good qulaity CDRs from two different brands/batches.
I also happen to have the a second drive in my computer (not RAID) dedicated to backups and quick recovery. Then there's also an external Firewire portable HDD that is another copy of the backup. I say you can never have too many backups.
This is how I backup my precious photos. For regular data, all of it fits on one CDR so at least once every month I write a full backup to a CDR. The CDR has got to last at one month right?
As for MP3s... that's what P2P is for.. distributed backups.
Did you read the user guide?
http://www.e68.com.tw/circle-user.htm
yeah. lots of them. look how many floppies are necessary to store only 1 CD in this picture
Imagine how could be to store all the CD's you have. heh.
that work fine. I've never had a cd that just decides to become unreadable.
Having worked at a CD manufacturing plant for some time, let me reiterate what we already know here. The actual cost of the CD (physical media and pressing) is a negligible part of any CD-based product that you buy, whether it be a music CD or a piece of software. You could double that cost and the price of your end product might go up by a nickel. While it's true that in business we shave every cost that we can, it's not much worth bothering with that if it's going to have a big impact on the quality of the end product.
Another point is that cost is small compared to the cost of silk-screening, transport, the packaging, etc.
The manufacturers don't want built-in obselesance. The simple fact is that most of today's music has that feature aside from the media.
I've yet to have problems with CD's, even ones that the kids are abusing. Are you?
Do you have ESP?
I really do wonder how this guy offended any moderators.
I honestly used to believe that moderators were supposed to be moderate.
Anyways, back to the topic at hand, yes, I think he's onto something. I'm observing a lot of friends having to replace their 48x discs rather often; like, to the tune of six months.
Now the only thing I'm worried about are those cyanine-loving bacteria. If I can protect against those, then I can keep a CD healthy. After all, I've been using some of the same CD-Rs for three years quite actively, and they are yet to die. But I should get around to making permanent shelved copies...
-
And the Angel said unto me, "These are the cries of the carrots! The cries of the carrots!"
Fuji is made by Taiyo Yuden. TY makes high-contrast blue CD-R media that is ideal for archival use. TY is also making some Memorex, believe it or not. Just make sure when you are buying a cakebox that you check where it's manufactured. If it says "Made in Japan" it is more than likely TY made the disks. If it says "Made in Taiwan" move on. It's the cheap stuff out of Taiwan you need to worry about.
If you are really concerned about archival stability, Mitsumi Gold and Kodak are what you want, although I don't think Kodak is available anymore. I understand that Mitsubishi Chemical's disks are also quite good for long-term archival use...I just won't touch them because Mitsubishi is one of the most evil companies on the planet.
Oh yeah...a CD-R burnt at 4X is just fine for long-term stability and maximum compatibility too. It's when you get to the "ludicrous speed" of modern CD-RWs that you begin to have to worry about compatibility problems.
Knowledge is power. Knowledge shared is power multiplied.
Also, how were they all stored?
I keep all my CD-Rs in those book-like carrying cases from CaseLogic, etc (sheets of plastic/vinyl CD sleeves with soft coth backing). I keep the books closed and tucked on a bookshelf unless I'm actually retrieving or replacing a CD.
In my experience with CD-Rs over the last 10 years, you have to get many factors right for longevity:
- store the CDs in a temperature-controlled, dark place. Jewel cases are actually the worst way to store them, as they let in light and air, offer little protection in event of a drop or crunch, and unnecessarily take up more space.
- get CD blanks that have a thick enamel/paint layer over top of the metallic layer... most brands don't have this, although some (Verbatim DataLife Plus blue-bottom with the white enamel layer) do. For safety, what you do is get some of those CD labels that you normally use in a printer to print your own labels, and stick them over the disc. It provides added structural support and protection from UV rays, heat, etc to keep the metallic layer from crackling or flaking off the disc (which is usually how blanks go bad, in my experience).
- If you want a CD to last, burn it at half its rated burn speed or slower. If you burn a 48x disc at 48x, don't expect it to last too long, because the burn didn't "set" as well. (I don't know the technical details, that's just what I've noticed from experience).
- Use a decent burner. Plextor makes the best, or did for years at least, but generally speaking you just have to buy one that is capable of jitter-free, error-free data and audio ripping. (The drives that rip better are generally tracked better, and thus tend to yield better burns as well, I've noticed).
- Don't rely on BurnProof, JustLink, or other such features during a burn. Sure, it may be handy and deliver a working disc, but the way those technologies work results in a less homogeneous burn and the disc doesn't last as long. These technologies are just lazy-man's excuses to avoid purchasing fast-enough hard drives anyway.
These are the general rules I follow, and I have plenty of discs that are 5-8 years old that are still fine, particularly the Verbatim DataLife Plus discs with the blue-bottoms.
Moderator hint: a comment is neither "Flamebait" nor "Troll" if it is true.
One other point. Pressed CD's don't have a dye layer, which calls into suspect your entire post. They start off as a simple transparent plastic disc (I probably have one around here somewhere), they are pressed (literally) to get the indentations for the data, then they are covered with a reflective aluminum coating. It's literally aluminum metal; it's not going to degrade any time soon.
Michael
Do you have ESP?
Read at -1 and you'll find this isn't exactly true.
If your theory is different from practice, then your theory is wrong.
And you store all of this in one room in your house. The first fire will ruin all of your effort. Time to hire a company to do off-site storage of backups for you.
which is a completely ridiculous notion. Well no, let's not be so aggressive, it's not COMPLETELY ridiculous. But if that reasoning was all true, if the laser had the time to burn a pit normally at 1x, then that time would be divided by N at Nx speed (well not exactly, but that's beyond my scope), and the pit would be N times "weaker".
So of course, the power of the laser is increased to palliate this effect.
So in an perfect world, the laser power would be increased 32 times when you increased the speed 32 times, thus making the same pits as if you burned in 1x.
Now this is only taking into account laser power when burning at higher speeds. Thing is, there can be lots of other problems when burning at higher speed, any minuscule glitch in laser power, rotation speed, laser position, anything can cause a problem. Of course most problems are corrected, and those that pass aren't fatal. But with age, the organic compound on which your data is written deteriorates, as any organic compound would, and the errors get worse.
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
X-CDRoast does verifies.
There is one thing that unites us all- our love of pornography.
What a silly thing to say. Taking it seriously for a moment - There are lots of people who disapprove of pornography, for one reason or another. The political left (feminism) considers it exploitative, the political right (conservative religious) consider it amoral, and women (even geek women) don't tend to be consumers of pornography. Since Slashdot certainly has its share of political left, right, and women, it's easy to see that no one thing will EVER unite ALL Slashdot readers.
That being said, posts about pornography don't get modded up to +5 Funny more than any other running joke. It hardly takes the entire Slashdot community to moderate a post to +5 Funny, and it doesn't happen any more often than your obligatory Simpsons quote, or CowboyNeal reference, or beowolf cluster, etc.
Experts agree: everything is fine.
Using Grease to seal a CD-R?
You mean encoding selections from the 1978 John Travolta and Olivia Newton John movie on the outter tracks of the disc? Brilliant! Even O2 won't react with John Travolta.
As far as removing Grease, the Church of Scientology can remove anything it wants. Its the perfec solution!
Troll Like a Champion Today
It has been well known for years the regular CDs also deteriate. I have ALWAYS instructed my non-technical friends and family to forget using CDs and simply backup their entire hard drive to an equal or larger capacity external drive - and keep it in a different building to the source material in case disaster strikes. A lot more convenient too. slashdotalex@owonder.com.
O'WONDERWe're working on it.
"Error distance" is nonsense. First of all, the turn on and off time for solid state lasers is miniscule. Second, this "error distance" is the same over the entire disc, and the on and off time should be roughly equal, so at worst you would have the pits "skewed" or delayed in relation to the actual input data. So what? The problem with the test was the variability of the the CD blanks. Cheap discs are cheap discs. Don't expect crap to last as long as name-brand media.
I can't beat it, but I also have floppies from the mid- to late 1980's which read fine. My oldest CD-r's are June 1995. Verbatum disks. I pull disks out from time to time when I need an old customer file and my CD-s so far have not been an issue. I pulled 2 from June 1995 and copied the contents of each to my hard drive without a problem. Every file copied and the few I tried opened just fine. I do keep my floppies and CDs boxed in a closet.
Hey Beavis, What's in Olivia Newton's John?
Heh, heh, I don't know Butthead.
Gomer's Pile.
Q: Why is that?
A: Top posters.
Q: What's the most irritating thing on Usenet?
-- This and all my posts are in the public domain. I am a lawyer. I am not your lawyer, and this is not legal advice.
Finding removable media is such a pain however, so I replicate all the critical data between systems using RSYNC to both the Linux server, the NAS *and* my primary desktop. I also have smaller RSYNC routines to keep critical data upto date on the laptops and the secondary PC. The upshot is, from any PC connected to my home LAN I have a choice of three copies of the data just by CDing to the relevent shared directory.
I think, given that I'd have to simultaneously lose my Linux server hard disk, primary workstation hard disk *and* two drives on the NAS RAID to have a problem my data is pretty safe. Oh, and before anyone mentions fire or some other disaster, a copy of the ZIPs and the CD-Rs are at my sister's and I have a copy of her data here. You can tell I've lost a lot of data in the past, right? ;)
UNIX? They're not even circumcised! Savages!
Does it matter? Yes. Is slower always better? No.
Rather than re-hash this, please see:
In the CD-Recordable FAQ.Quick summary: higher speeds require a different "write strategy" than slower speeds. Different media formulations are optimized for a particular write strategy, so writing slower than the optimal speed can actually produce inferior results.
The choice of media and recording hardware has to be taken into consideration. In any event, this has relatively little to do with disc deterioration. A disc that's better to begin with won't show the effects of physical deterioration as soon, but if the top lacquer coat isn't as close to air-tight as materials allow, it doesn't matter how you write the disc.
Roxio Toast Titanium on the Mac also has a verify ability - it offers you the option of verifying your disc right after burning and will do so if you don't respond in 10 seconds or so.
Mac OS X has CD burning ability in both the Finder for data and in iTunes for music, but even so, Toast is well worth it.
It is absolutely true. It becomes increasingly difficult to create well-formed pits at higher rotation speeds due to the more difficult timing tolerances. Also, it is easier to get predictable burn results at a lower laser power setting.
does toast lite verify? I have not had a chance to instal it yet with my new external laCie burner.
I am the Alpha and the Omega-3
Which doesn't make sense, since most manufac. specs are 100,000 hours Mean Time Between Failures.....or 11.4 years
I can hear the party at Hillary Rosen's house from here.
There is nothing so powerful as an idea whose time has come.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Who cares if the media will still have errors 100 years from now, if there won't be a drive to read the disks? Surely, you don't think there's going to be any working 14" WORM drives. Even if they archive the drive, they would need a working computer with an appropriate interface to plug it into.
Anyway, my point is that, while it is certainly important to have high-longevity archives, they will have to be rewritten with more modern media every 10-20 years just to keep their media up-to-date with the computer systems that have to read them. Of course, the same goes for the data formats themselves.
aQazaQa
CD-RWs are extremely photosensitive.
Though I always make multiple copies of really important files, the brand of CDR is very important.
I have 8 year old Sony CDRs that still work perfectly. That's a brand I really trust for long term backups.
I also have had lots of ~6 month (or less) old Memorex CDRs and they've been extremely unreliable for me. I've sworn them off.
TDK's are cheap and what I usually use. No problems at all.
The biggest benefit is that it cuts WAY down on the number of +5 posts, so you can get straight to the key comments if that's all you want. It's cool when the home page says "24 of 215 comments" but when you click in the Funny modifier filters half of them out and you end up only having to plow through 12 :)
One simple rule for its versus it's
There you are not correct. On what you call the data side the data is protected by a thick layer of plastic. On the other side of the CD, the label side, the data (the pits in the metal layer) is only protected by a thin layer of plastic. So scratching the label usually does a lot more damage than scratching the other side of the CD. So the sticker has to be applied to the label side. It is transparent so you can still read the label after application. Scratches in the thick protective layer on the data side can be repaired by filling them with a material with the same refractive index as the CD itself. There are also kits for that. I'm sure you can find them using Google.
-- Cheers!
Same here. I've got disks from when I got my first CDR. Was just using one the other day. My guess is the failures are if you use unbranded disks on an unbranded drive. I had one CDR drive that was AWFUL. You'd burn a disk, eject, put it back, and it would think it was an audio CD. Terrible drive. Disks burnt on that drive are EXTREMELY flaky.
Actually, thinking about it, I do have a couple of disks that are tough to read, but the fact is they've been like that from day one.
In the begining, the media was new, and people bought what was available, and I'm sure they didn't have the best inks for the intermediate layers ready just yet. Eventually, these will decay. And as more and more vendors got into the game, do you think their major focus was extending the lifespan? No, most likely it was cutting costs without majorly effecting lifespan, only making them last longer where economical.
That being said, if thise gets noticed by the big media folks, I wouldn't be suprised to see 'premium' cdr that advertise a lifetime of 5 or 10 years, for 4x or more in cost, or at slower speeds or some such.
No I haven't :-( But at the CD rental service where I worked they always protect the label side with a plastic sticker to prevent scratching of the metal layer like I described. And you can of course stick the stickers described on e68.com to the label side in the same way as they show. I think that makes more sense anyway.
-- Cheers!
Yes of course, but the parent's comment "If you burn the CD at slower speeds, the laser has more time to burn better pits in the media." is wrong by saying it's a problem of "time to burn a hole". As this comment and you correctly point out, it's more a question of errors relative to speed.
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
I've heard that CD-RW discs record data by litterally melting pits into the reflective layer, as opposed to CD-R discs which use a dye that changes colour when exposed to UV light...
Would this mean that CD-RW discs are more reliable for long term data storage?
What? Me? Worry?
The silver salts used in black and white photography have a known life span of over 100 years. Instead of dyes, use silver halides! A problem may lie with Polaroid patents.
This article simply isnt true, i still have my pr0n archive from 2000 backed up on cd, and its all right...
OH NO!!! My pr0n! My precious Precious pr0n!!! Damn cheep cd's!!!
Noone writes jokes in base 13!
No shit. I have a file serving tower with 500GB of disk space in it, and it's 80% filled with pr0n. I also have 250 full CD's of backed up pr0n, coming to a grand total of almost 650GB of hardcore stuffing. Since the drives are almost full, I'll have to do another 100 disk backup soon. I was holding out for a DVD writer...mmm...4.7GB of pr0n per disk...think of how much more I can download.
PS-Yes, I'm sick, but I got tired of kids in highschool always boasting they had "over 150MB of porn movies" on their computers. So I put them all to shame. I mean, is there any greater feeling than knowing you pirated a good portion of the T&A industry?
-
MAM-E Gold Ultra, about Eur. 1.15 each.
-
Mitsui Gold Ultra, about $1.60 each.
Kodak used to be in this market, but seems to have exited it.The key here seems to be dye type. Phthalocyanine has slower writing speeds but longer storage life; Cyanine has higher writing speeds but much shorter storage life. The "archival grade" CDs also have gold reflecting layers and a tougher substrate.
There are also "Medical grade" CD-R blanks, but they're essentially the same as the archival ones.
There are programs which will read the ATIP information from a blank, telling you what the manufacturer, max writing speed, and dye type is.
I've got several CDRs that are five years old and much older, and I ran KProbe on a handful of the oldest ones to see how they're holding up. They exhibit pretty much the same amount of errors as any disc I've burned in the last week. Don't buy crap discs.
I've thought of that from time to time, if you can find an appropriate ink on acid-free paper. Not a laser printer -- the toner does wierd things in the presence of whatever fumes vinyl gives off.
Back in the early days of microcomputers, one of the magazines (Dr. Dobbs? Kilobaud?) used to publish "machine readable" code alongside its listings of BASIC programs -- some kind of B&W bar or matrix code. I don't recall how you were supposed to read it.
-- Alastair
I have seen this. I have a music CD that has visible "pits" in the aluminum from oxidation. There does not appear to much (read any) protective layer on that CD at all.
Are you talking about a CD-R or a regular pressed CD you buy from the music store?
Most CD-R's have no protection at all because the foil and top label/paint are stuck together on the top of the disc. However, I've never, ever seen a real "pressed" CD or CDROM that was made that way. They all have the protective plastic coat on top of the foil.
Regarding Mitsui (arguably the best CD-R maker) leaving the market...
I believe an Italian company has licensed Mitsui's CD-R technolgy and will keep on making the discs.
http://www.mitsuicdr.com/ has some details on this, but it's kinda vauge. The new name appears to be called MAM Gold CD-R.
In retrospect, one of the first signs that my Yamaha CDRW was going tits-up, was that the disks it wrote went bad inside of 6 months. They looked perfectly fine at the time.
I'm quite glad that I have the paranoid habit of making duplicates of archival CDRs, because in some cases, only one of a pair went bad.
PS, my "known prematurely-bad Yamaha drive" count is now up to 19, with ZERO known surviving to a reasonable age (in fact, most didn't make it out of warranty alive).
~REZ~ #43301. Who'd fake being me anyway?
Why not use mirrored disks for backup? Although you loose protection against accedently deleting files, you gain a constant back up and possibly faster read times with minimal effort.
than a placebo when used as a backup. If you are concerned about your data you need to keep a copy elsewhere, not on a RAID array.
Hello,
Could you reference your comments with URLs to websites to back up these statements.
For example, just exactly why is Mitsubishi 'the most evil company on the planet'? I'm not defending them, I simply want to know what could compell you make such a statement.
Also list websites that provide more info on the research to led you to state that Taiyo Yuden's high contrast blue CD-R media are ideal for archival use.
Again, I'm not challenging your assertions as much as looking for both conformation and information on the best way to approach getting around the problem of CD-R degeneration and data loss.
Thank you,
Simonetta
Toast Titanium on the mac has a verification option as well. And here's something interesting: I must have burned and verified hundreds of CDs over a period of about 3 years and in all that time I have only had ONE error detected during verification. It as on a 12X Verbatim CD-Rw that I burned at 12X. (This was only the 2nd or 3rd burn for that disc.) I burned it again and it was fine though.
(Of course this was just one sample and it does not lower my opinion of Verbatim as a brand.)
Mitsui is currently the only company making archival quality CD-R media with a phthalocyanine dye layer and a gold reflective layer.
All archival quality CD-R's use phthalocyanine, it is the only stabilized dye known to last more than 100 years. Gold is the absolute best reflective layer available because it is almost completely non-reactive.
The combination of those two is the only way to get a true 200 year archival life CD-R. They aren't "cheap", usually less than a dollar each but 85 cents in a 100 pack isn't unusual. Try this google search. The second link is a place selling 100 packs for $82. That's 82 cents a piece for a CD-R that should last until the year 2200.
If you're willing to live with slightly less... I managed to pick up a pack of Fuji CD-Rs with a phthalocyanine dye layer and aluminum reflective layer. Fuji seems to think they will last 100 years, but I have my doubts. Still the #1 reason CD-Rs fail is the dye layer, not the reflective layer.
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)
According to this ancient Seybold report, Dataglyphs can achieve densities of a kilobyte per square inch.
DataGlyphs were featured in this /. article about chess playing scanners.
Bleh!
You can't estimate the disk corruption by comparing MD5s. You can know if the file is corrupt.
There are tools, I believe, that can investigate and display the extent of the bad blocks. Maybe someone has a link to one.
Fuji is made by Taiyo Yuden. ... TY is also making some Memorex
Both Fuji and Memorex have TY and non-TY discs. But you can, as you say, check the packaging for the country of origin. As far as 50- and 100-spindles go, every "Made in Japan" I've bought from these two brands has been TY, as reported by CDR Identifier.
--
Dum de dum.
Freedom is not the license to do what we like, it is the power to do what we ought.
>I'd explain, but it takes too long given that I'm typing one-handed.
you're wanking over slashdot comments?? yikes.. desperate times..
xcdroast and many others do verify content after burning.
Windoze isn't the only thing around and there ain't any linux version of nero. Perhaps if you choices of cd burner programs are so limited it might be a clue that it should be time to think about a better operating system.
Except this article seems to indicate that the quality of the CDR media deteriorates over time. Even if you verify your recording after it's completed that's no guarantee the disc will still be readable in two years.
In that case, why not place them in a Faraday Cage. Seems easier then rotating every month for a century.
Checkout 2D barcodes such as QR-code, DataMatrix, and MaxiCode:
here
QR-code can store 2,953 bytes in a single code.. I'm not sure what the size of the code is, but looking at photographs of it shows that it is "damn'ed small".
I have some backups of some 3D graphics work that I worked on that were put on to CDr about 5 years ago..
Pulled them out for a new client, totally unreadable..
In a panic I checked others with varying results.. Using an older 2x drive to read them helped a lot, but a few disks were toast.. All were supposedly good quality brands..
---- Booth was a patriot ----
"Q: What size of QR Code can be read?
A: Readability depends on the module size and operating environment, for example, if a module size is 0.5mm (19.7 mils) square, the readable QR Code size is 105 x 105 modules (52mm (2.0") square) or less."
It seems that you can print on arbitrary module sizes, but it's readability depends on the quality of the scanner.
These CDs WERE NOT WRITTEN TO. They were stored on the original spindles for 20 months and then HARDWARE ANALYSED. The CDs were all completely blank.
[insert witty comment here]
I really do wonder how this guy offended any moderators.
I honestly used to believe that moderators were supposed to be moderate.
I have the answer, people are fucking with the system, someone creates multiple accounts and posts round the clock, and harvest mod points and screws with his/her foes, it is just pathetic how people spend their times, I have been systematically hit by an "overrated" and "troll" moding for the last month, I just smile when I see this, it makes me feel important that someone will go through all this trouble just to mod me down.
Green CDs have a life of ~5 hours. Yellow CDs ~20 hours. The DARK DARK Blue cd's
I'm curious where you got that from. The original "Golden" CDRs were absolutely awesome, or so I found. Not once did I ever have a problem reading them with anything. They were expensive though.
Some CD-R brands already have this built in. It seems that Taiyo Yuden has been making some improvements to their production process in this respect. For quite a while, I've been burning on 24X FujiFilm made by TY, but my stock of that recently ran low. So I bought some more spindles of TY/FujiFilm but rated at 48X. When I opened them, I noticed that the tops were a lot shinier than the 24X. Upon closer examination, I noticed that there was actually a hard layer on the top, probably designed to protect the data layer.
toast also verifies cd-r's fool
From a little googling, I now see that they signed a Memorandum of Understanding with the Rainforest Action Network promising to change their ecologically unfriendly corporate practices. Here is the link:
http://www.ranamuck.org/news7.01mitsi.htm
Provided the humungous Mitsubishi zaibatsu is living up to their promises, I have no problems now recommending Mitsubishi Chemical CD-Rs. Everything I said about TY goes double for their disks.
The reasons why TY and Mitsubishi CD-R blanks are so good and so compatible are the fact they use a much darker dye than the Taiwanese manufacturers do. Yamaha suggested the use of Mitsubishi Chemical CD-Rs with their "Disc T@2"-equipped burners because the graphics would show up better. They are a better choice for maximum compatibility for the same reason they are a better choice for "Disc T@2". The more visible the dye layer is to the naked eye, the more visible the dye layer is to a CD-ROM or CD player's laser.
I wish I could back my assertions up with a whole list of studies, but I am basically speaking from several years of my own experience with CD-R blanks. I don't see as many CD-Rs made by TY going bad as no-name Taiwanese crap does.
Knowledge is power. Knowledge shared is power multiplied.
A very poorly researched article, by a Dutch magazine that already had a not-so-good reputation (these guys aren't even in the same league as say the C'T magazine)
They hardly give any real test condition data ("stored for 2 years in a closet" isn't very detailled IMHO) All I know is that every CD-ROM / CD-RW / DVD-ROM drive I own can still read even my oldest CD-R disks I have, which are old 1996 disks which back then were only suitable for 1-speed writing and cost over $5 each...
I left my CDR's out for about 3 weeks and
check out the results:
http://www.techfreakz.org/cdruv/
These are name brand CDR's exposed to the
sun for only an hour or two each day.
(mod this up guys, people need to be warned).
Also, what happens if you're storing source code and you discover an error that was introduced into a project two months ago. With a good tape backup rotation you'll be able to restore the correct files. If you just keep a single copy, you won't.
I can say this because I used to do sys admin work for a software company, and scenarios like this used to happen occasionally. I always kept daily/weekly/monthly rotation cycles and was able to restore any file for up to a year, with checkpoints beyond that time. I also kept off-site backups in case of some disaster to our office.
Backups aren't just about keeping a copy of your data in case a disk drive blows, they're about archiving your data for future retrieval. Disks drives just don't cut it, unless you're willing to keep a few dozen disks sitting around for every one you need to back up, and you're willing to haul them back and forth from some off-site location. In the long run, using disks for backup is inefficient and expensive.
Unfortunately by the time my older 1541 drive started going out of alignment, there was no such thing as a "Commodore Authorized Repair Center", and I didn't have the necessary tools to accurately mess with the stepper motor.
Re-aligning the drive at that point consisted of loosening two screws on the stepper motor and running a program that would constantly query the drive to see where the drive thought the heads were, versus where the program thought that they were. Alignment was achived when you reached as close to the two numbers as you could.
I could never get the drive fully aligned, I was always a half-track off, either on the upper tracks or the lower tracks. But, it worked well enough.
The 1541 series drives (and even the later ones) were excellent pieces of machinery. They were completely programmable, the head could recognize half-tracks, and because of their programmaility, you could do all sorts of neat stuff with GCR data (densities, etc.), making disks that the drive itself couldn't write, but could still read.
-- Joe
To vary from that.. Actually, the copy protected cds vary too so they should not have the logo. But they have it still afaik.
Tape drives still are the "big thing" in backup if you care at all about your data. Today's tape drives have huge capacity, are very fast, and the tapes last for decades.
Some people whine about the cost of tape drives and tapes, but it is more than worth the money if your data is important to you.
Your porn is worth the cost!
so reading slashdot is the new geek pornography?
Not only that, but especially considering that it wasn't the slightest bit funny! Sheesh! It's not like he told a joke that was going to make us burst our sides laughing, which is what a +5 Funny should indicate.
I was going to mod it Overrated, but decided to reply to you instead.
This is where you scream and yell at me :) It was from verbatim sales literature :) It sure as hell matches my observations though. *None* of my greens still work, some of my yellows work, and all of my blues do :)
Religion is a gateway psychosis. -- Dave Foley
> What speed was used to write the CDs?
The article doesn't say.
> Were they all stored in the same place?
Yes, stored in a closed dark cabinet since they were burned 20 months before.
> Were they all burned by the same CD burner?
That's likely, as it was a media test.
> Were they all burned from the same source (a single CD, hard drive, network, etc.)?
I don't see how that is even relevant, but that also seems likely.
Burning conditions are likely to be accurately duplicated for each of the CD-R's as it was a quality test of the media 20 months ago. It wouldn't do to use different testing circumstances. They claim to have stored these media for 20 months locked up tight, and now tested them again.
The article doesn't go in much detail about the results, but claims that a significant portion of the CD-R's tested were badly degraded since their initial test. In other words they were unreadable in some areas or a lot of error correction was required to get valid data -- they used a reader which can distinguish this.
My personal experience with CD-R's is not unlike this article. I have about 100 CD-R's of varying quality created about 5-6 years ago purely as backup (ie, they were never used after initial burning). They were stored in a closed box (I never left them lying around after backup) in my own home under normal circumstances (not refrigerated or anything).
Not too long ago I tried restoring the data, and found that almost all discs had problems reading, especially the files that were on the outer tracks. In most cases it was only possible to recover about 75% of each disc. Some of the discs had visible defects (bubbles, decolorations). Only a handful of discs were 100% intact. I used several different drives to read these, and had the best luck with CD Burning drives (mostly Plextor stuff), but even those would give up even though they could usually recovered 50-100 MB more than my other run-of-the-mill CD drives. The CD-R's I used were of varying quality, and I definitely bought a bad batch of about 25 orso (all badly damaged) -- none of the different brands and colors of discs I used seemed free of problems though.
OT, but seriously, I loathe bottom posters. Because of them, I have to click "read more of this message..." on every friggin post in a thread on google groups (still deja to us veterans).
Bottom-posting advocates think in the best interests of the 15 people who still use news-readers (and not even then - anyone following a thread knows what's been said. it's faster to read the top couple lines only...). But they neglect the thousands who have to wade thru all that crap on the web.
Chop or top-post. Never bottom-post, people.
Why not just get a fireproof safe?
Remember that the objective here is long-term archival backup, not fast online backup. That also means that your backup system doesn't need to be running full-time, so the lifetime of the drives can be a lot longer, and you can use large drives instead of needing the fastest drives out there. On the other hand, there's the risk that you'll need to keep a computer around to run those drives, because technology change might make those drives unreadable on newer computers. (The opposite happens as well - I'm having trouble using my new 120GB drives on my P233 machine, and I'm beginning to suspect that it might be the internal cabling in the removable-drive drawers that's causing errors.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Do a full backup once a year and a 20 month lifespan for the media doesn't matter...
Maybe not. The 20 months is just an abstraction for when the media has reached a far stage of aging. Of course, in reality, it ages continiously.
Making a copy after 10 months (of a half-aged) file does not solve the problem unless you have a scheme for recovering everything that has been lost during the first 10 months.
There are such schemes; essentially if you build in redundancy in the data and restore it when you copy. I don't know if these are commonly used by standard file formats and copy programs though (Anybody knows?).
Tor
Actually, they have the "compact disc recordable" logo, which, obviously, has different specs than a pressed CD.
You can't restore any version of a year-old file, just some version that was current one day that month. And why are your users waiting for you to dig out old media rather than using a version control system with fully online storage?
Wow, nice user id. :-)
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Uhh....actually, there are no pits being burned in the media. It's rather a phase change in the plastic that either leaves the area translucent or makes it opaque. Stamped CD's do have pits...as they are pressed by a glass master in most cases.
"The strong will do what they want, the weak will do what they must."
-Thucydides
"I seem to have mastered a certain amount of control over physical reality."
I've got crap that was recorded on a funky 1x drive back in 95-96...
works fine.
CD-R ROT
CD-R's unreadable after two years
Sample reveals disturbing results
by Jeroen Horlings
Valuable data on a CD-R are in practice not infinitely durable. From our laboratory tests, which will be published in the September issue of PC-Active, one can see that the data on a CD-R can become unreadable within two years. There is a great risk that by using certain brands of CD-Rs important personal information is lost.
As our readers of PC-Active will probably know, we conducted and published a large number of CD-R tests in 2001. From that it became clear that new CD-Rs did not satisfy quality standards. We kept the thirty different brands which we had investigated that year [2001] for two years in the original packaging in a locked closet. For the article `CD-R ROT' [whose online summary you're reading] we subjected thoses disks to another test with a professional CD analyzer which examines bit per bit what the state of the CD-R is.
[Image: November 2001 vs. now. Caption: In this figure you see the exact same CD-R. On the left you see the result of the test in 2001, on the right the same CD-R in 2003. The colors indicate the seriousness of faults, in the order of white, green, yellow, and red. They stand, respectively, for `well readable' (white) through `unreadable' (red).]
The test shows that a number of CD-Rs had become completely unreadable and that for other CD-Rs the contents had become partly unreadable. Data which had been written to CD-R twenty months ago had become unreadable. This involved CD-Rs from well known and lesser known manufacturers.
It is often assumed that CD-Rs are durable for at leat ten years. Some manufacturers even claim durability of one century. Our sample shows that there is a lot of rubbish in the market. We encountered CD-Rs that should never have appeared in the market. It is unacceptable that CD-Rs have become completely unusable within hardly two years.
The September issue of PC-Active, which will be available starting August 22 [and costs 6.99 euros], contains a comprehensive description of the schocking results. To reduce the possibility of loss of content over time, we also give a number of valuable tips for keeping the contents of writable CDs safe for the future. The free CD-ROM contains contains a program with which one can ascertain the state of CD-Rs.
The political left (feminism) considers it exploitative
a-ha, but that depends on what kind of feminist though. and feminism isn't intrinsically left wing either. you get capitalist (right wing) feminists too.
MilkMiruku
a while back http://www.cdmediaworld.com/ had an article explaining how there were something like 256 different brands of CD media, but only something like 16 different manufacturers of the actual media.
Taiyo Yuden were reckoned to be the best manufacturer. they make discs for lots of different manufacturers, but you don't know 'til you get home and get yr CD writing software to read the code off the disc and tell you who the manufacturer is, bcos it aint gonna tell you on the packet. and different sub models of disc can be made by different manufacturers.
I think TDK even had the same models, with some made by Ritek (the worst quality) and some made by Taiyo Yuden. there was a court case against them for this.
I buy a single TDK disc, take it home and check it, and if its made by Taiyo Yuden I go back and buy loads of that same model disc, and have been able to get the people in the shop to say they'd take the discs back if they weren't Taiyo Yuden (a large consumer-space chain in the UK, I shan't name them incase they read this and stop being so remarkeably fair)
All I know about Bush is I had a job when Clinton was president.
If that's really all you know about Bush, perhaps learning more might aid your job search.
I have CDRs that I burned just under 5 years ago that I frequently use. They all appear fine.
Tp.
Mirror #1 HTML PDF
Mirror #2 HTML PDF
Mirror #3 HTML PDF
Be realistic, how many of those people do you think hang out on /.? Hands up all you feminazies, radical fundies and female geeks who never, ever consume pornography in any flavour.
Yah how much longer before we hit seven digits. Who would have thunk this thing would have so much staying power.
But doesn't the thickness of the laquer affect whether or not a scratch will be fatal to a CD? I have some pressed CD's from the early 90's that are rather thick looking compared to current ones. They're covered in scratches but still work, where as more lightly scratched CD's I've bought recently fail..
I purchased CD-RWs because I suspected they would last longer than CD-Rs they use a crystalization process instead of dyes. Does anyone have any data on how long CD-RWs last?
It's not like he told a joke that was going to make us burst our sides laughing
:)
How very true
I have CDs that have over 7 years and I still can read them perfectly... maybe is the quallity of the CDR that they use?
:: Andrea
Anime Wallpapers
Quite true! The same argument applies to anti-pornography conservatives, as well. However, for the purposes of my (rather simple) argument I just made a generalization. Which should be allowable because it's ultimately not very relevant to my original point.
Experts agree: everything is fine.
PATENT THAT IDEA!!
Fast, before somebody do it before you and in 5 years you will be able to sue corporations to:
3- Profit!!
Yah but is it redheads or blonds?
It's cool when the home page says "24 of 215 comments" but when you click in the Funny modifier filters half of them out and you end up only having to plow through 12 :)
:)
Jokes are usually short one-liners, so the actual amount of content is not cut in half by far. I think most people could use some comic relief, even if some of the gags are bad. If you can't either laugh with them or laugh of them, lighten up a bit
Kjella
Live today, because you never know what tomorrow brings
Of course - being realistic, you're right. There can't be any sort of those people on Slashdot.
Oh wait, except I'm one of them.
Congratulations and welcome to my foes list, dick.
Experts agree: everything is fine.
Something else I should have said ...
A couple days ago I posted a message in a SCO story that linked to this. I expected it to be modded Funny, but it didn't get modded once!
Now this post that says nothing but "ooooh my precious porn" gets a +5 Funny. Good grief!
Comment removed based on user account deletion
Apparently. They seem to have switched from the "metal azo" dye to "super azo" whatever the fuck that means. Too bad, I hate to see a good product die like that, hopefully the blues are still avaliable (bulk orders maybe?).
Thanks for the heads up. I still have a cache of them I got 3 or 4 years ago when they were on sale :)
Religion is a gateway psychosis. -- Dave Foley
Yes, but were they still readable?
Same here, I have CD-R's from my Ricoh CDRW (the first one on the market) that are now 6 1/2 years old and all of them that aren't scratched to hell are still readable. I wonder if this isn't indicitive of a falloff in quality of blanks. Back then blank CDR's were over a buck a piece and to get ones that would read in most normal cdrom or audio players you had to pay around $4-5 a piece, now you can get CD-R's for around 5 cents a piece. Obviously scales of economy have dropped the price but I'm wondering if cheapening of materials has not also been a big part of it.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Oh no, I think you hurt his feelings. Boohoooo
>Why is it that standard CD-ROM hardware will not allow us to do this?
Somebody thought that no one would possibly want to do such a thing so they never programmed it.
Go here to create your own Slashdot dis
Just memorize it. It's all ones and zeros anyway, so it should be simple enough.
Close, but actually it is inducing a color change in an organic dye. This dye is either green (unburned) or clear (burned), and is sandwiched between a reflective and a non-reflective layer.
-- You are in a maze of little, twisty passages, all different... --
CDs do not make excellent coasters. They have no absorbant surface. As such, condensation pools on the the surface of the CD, and even drips off the side. I have actually watched a beer bottle placed on a CD slowly slide off.
They do, however, make excellent ceiling decorations. With proper lightiung, they can be quite shiney.
You are totally blocking my view of the wall. - Dogbert
Congratulations and welcome to my foes list, dick.
And I'm sure that mitheral will run home crying now.
Or how about just using a medium meant for archival storage like high quality CD-R's from name brand vendors and tape backup like DLT, LTO, or even DAT. Or for a cheap home solution get a decent sized external hdd and just do differential backups ocassionally.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I'm not positive, but isn't it a chemical change rather than a phase change? A phase change would be from one of the four states of matter (solid, liquid, gas, plasma) to another. My understanding is that what is involved is a dye undergoing a chemical change, not a phase change.
Quality is a dying industry.
i a/ Kodak.html
Kodak Gold Ultima CD-Rs were made using the same dye that Misui uses for their gold media. When my cache of Kodak media runs out, I'll start buying the Mitsui CDs.
Kodak has published some interesting test results showing that their Gold Ultima CD-Rs have error rates in accelerated lifetime studies that are comparable to pressed CDs when other product is degrading severely.
http://www.cd-info.com/CDIC/Technology/CD-R/Med
It is unfortunate that cheap crap at low prices usually drives the good stuff out of the market.
No, the laquer is on top, scratches affect the playability only when they are on the bottom (play side). Well, I guess except for extreme cases...
What you are probabably seeing is inferior pit geometry (i.e. at the low end of the spec) or other reasons, allowing scratches to have a greater effect. Machines nowadays make a disc in 2-3 seconds, as opposed to 14 seconds when we started, so they are stretching all the specs to gain cycle time.
...the CDR must be stationary and your system must spin around.
Because there's no "+1 Porny" moderation, and it's neither Insightful, Interesting, nor Informative. It's actually rather discriminatory that there's no way to find the good porn links posted to Slashdot. Damn puritan geeks.
This is true, and I wish Phillips would enforce it...but what do I know...
While I can't vouch as to whether a slower cd burner produces better cd quality, I can say that I have an old HP 2xWR and 4xR burner for many years, and even at 4x, I have had lots of flaky discs. How did I fight against this? I bought better CD's! Each CD is made with different materials, the blue and green are the weakest cd's with the shortest life span (one of those is worse then the other...but I forget which). Silver is in the middle, and gold is at the high end (reportedly platinum is better then gold cd's, but obviously not something easily found). In any case, when archiving media that is critical, I always opt for my more expensive sony CD-R's that contain higher quantities of gold, and that have that lifetime warenty for your media. Fuji is another company I have used as well, and their gold CD's have like a 500 year warrenty or something. Anyway...most of all my generic, blue, and green CD's almost all loose at least 1% readability failure within 3-4 years, but I have yet to lose data on the gold CD's.
Also, when I refer to the type of cd, like gold, it does not necessarily mean the entire cd is gold, but has gold substances in it, which makes the bottom of the cd have a gold apprearance. In other words, it is not entirely gold.
Okay, but in what way does linking to an antifeminist men's-rights screed illustrate your point?
Personally, I'm holding out for 7 digit user IDs until I create an account.
You'd be surprised - he probably will.
The "Foes" designation ought to be amusing, but it seems that slashdot people really, really want to be liked. Even by people they hate.
Actually, that is amusing.
How can you possibly have a userid that indicates you've been reading slashdot since the start (even if it were fitfully) and be in any way surprised by this?
And please don't suggest it used to be any better. I was here too - it wasn't.
What we need is to use hemp paper. Cared for properly, it will last thousands of years, and if you get sick of it, you can put it in your compost (unless the inks are toxic) and nourish your vegetables with it later.
It would be interesting to see how the CD's would behave if they were placed in a temperature-controlled, humidity-controlled environment. Would temps and humidity, also temperature changes day/night and summer/winter lower the life expectancy? Probably more than likely.
Another thing I never quite figured out is what the best containers are for the CDs. I thought a jewel case might be best, because the readable surface isn't touching the plastic; but there are also polyethylene CD sleeves, polypropylene CD sleeves, Tyvek CD sleeves, and probably other types of storage solutions too. It would be interesting to see if sleeves help extend the lives of CD-Rs - maybe air gets next to the readable surface when it's in a jewel case and degrades the surface?
This is the biggest problem with the CD-R market. There's no long-range consistency in the formulation of the discs. Even within the same line, by the same manufacturer, there will be formulation changes, even dye changes. Outside of the brands that make their own discs, it's even worse - you're at the whim of whoever the lowest cost producer was (ie, Sony's discs are outsourced that way.)
:P
I used to buy only TDK. Then I had to switch to Verbatim when TDK started getting cheap on me. Now I'm using Mitsui media. When I started burning CDs on my 2x burner (I now have a pair of 8x burners and a Pioneer DVR-105) I was reasonably confident my data could last up to 10 years (I burned 3 copies, on different brands of CDRs.) Nowadays I haven't a clue as to whether my data will last the year
Time to make a fourth copy of my data and put it on a removable HD...
Put one of those Martian wireless network drives in the garage for nearline semi-remote backups. For cheap offsite backups, get a safety deposit box at the local bank, and put a third set of CDRs there. Bonus is that the safety deposit box is usually in an air-conditioned and humidity controlled vault.
It matters because the reading laser has three lasers, actually: 1 that sits slightly ahead of the reading laser, and one that sits slightly behind, and they're offset to fit the curve of the CD (the front and back lasers dont read the information, they look at the strips and lands to help the reading laser stay on track).
So when it reads, if the laser goes off track in either way, one of the front or back laser would get too strong of a signal, and compensate, this ensures that the laser reading the CD is always on track.
The difference with the burning laser is that, since there isn't information already on the CD, those other 2 lasers can't keep it on track, so the faster you burn, the higher the risk of the burning laser going off trakc there is, and thus a larger chance of error.
IsoBuster
AT&ROFLMAO
I've got this stone tablet that ...
Exactly. I meant that according to the instructions on the site, the label was attached to the side the data is read from, not to the label, which is what I wanted to protect.
After reading previous posts on /. about media formats becoming obsolete (remember the BBC Domesday project?), I would do the following:
1) If you want to keep something for more than a year, make multiple copies (so if part of one copy goes bad, you're more likely to recover it from another copy).
2) Store at least one copy in a different physical location. But most importantly,
3) upgrade your media every few years!
If you had something important on floppies, they should have gone to tape or CD-R. If you have stuff on CD-R, make copies on DVD. In a year or two, when the "DVD format wars" have settled and a format (+? -? #?) has been decided, make new copies to that. In five years, when the carbon nanotube ultrahigh density static memory is available, make copies to that.
Remember, it doesn't matter if your Beta casettes full of "Buck Rogers" episodes are in perfect shape, if you can't find a machine to play them on!
I had some very bad disks, i could record them at high speeds but could read on the next day!(only could read until after some hours of the burning) then i recorded with very lower speeds and can read it until now, more than one year. Now, everything important i record with low speed ...
#1 - When archiving DATA, always verify the burned media against the original data. #2 - When archiving AUDIO CD's, I always burn two copies because I can't verify the data. #3 - If you burn more than one copy, then always use different vendors media for each copy, which should protect you from defects in a media lot. For me to reduce costs and raise the chance of future recovery, I burn 1st copy to a higher-quality name-brand CDR, then a 2nd copy to the cheapest sale-price CDR. #4 - Over the last 25 years, I've had problems with Floppy / Tape / CDR, and have lost very important information. Now that I follow the above tips, I haven't lost any important information!
The other poster is correct. While we did not examine CD-RW, as they didn't really exist at the time, and also violated a rule for archiving for the group we were doing work for, which is that you can change them undetectably, I would imagine they suffer from the same problem as other mediums. Panasonic's phase-change designs were excellent, and substantially more stable than MO-RW, but in the end, they were VERY sensitive to UV, which is why they were in cases that had shutters that had interlocks. CD-RWs don't have this.
These CDs WERE NOT WRITTEN TO
And here is the key.
I've seen other tests where CD-Rs can't be written reliably after sitting around blank for a few years or artifically "flash aged" using elevated heat &c.
That matters to me a bit, but what's much more important is how reliable the data can be read after *being written*, then stored for years.
I use Kodak pseudo-golds (they don't make the real gold on gold ultima anymore) for anything I care about. The discs should be good, but they are also actually made by Kodak. No problems with the manufacturer changing & the brand remaining the same. No research on who's selling the best Taiyo Yudens this week needed.
Oh, shit! Good things never last. Well, the folks I bought my last batch of Kodak's from have a replacement: Mitsui Golds
I don't abuse my "archival" discs, so I don't care much about scratch-resistance, which is all some "life" discs offer. I care about bit rot.
My MP3's are all on CD-R. I've recovered stuff off them from as far back as 1998 (when I started collecting) with no errors. Heck I recently copied 100 of them for someone and they were all fine. Maybe I'm just lucky, or maybe I'm careful and keep them away from sunlight in cardboard sleeves.
:-)
All my pr0n OTOH is archived on DLT
I've used some Mitsui's in my day.
;)
They fscking *r0x0r*.
However, here's something funny - I have more than a few cheap silver discs that are five years old. They still work flawlessly.
Green discs? Still fine. Gold discs? r0x0r.
Hell, I've re-writables with 10+ rewrites, and they're still kicking.
Frankly, I think the real problem with CD-R/Ws going bad is a) people leaving them in the sunlight or heat or the freezer, and b) idiots who think their $40 cd-rw drive is 'high quality'
Yeah, were they readable? The part you show being discolored is just the protective lacquer on the top. (And IIRC the lacquer is actually an ultraviolet light-cured plastic, so it's not at all surprising that sunlight would continue the curing reaction.)
-- ;-)
Kuro5hin.org: where the good times never end.
Maybe CDs burnt at higher speeds have a shorter lifespan.
Toast for Mac has verified ever since I first started using it, 1997-98.
Dear Slashdot: next time you want to mess with the site, add a rich-text editor for comments.
You need deltas. What happens if someone, benign or malicious, changes something and you don't notice for a week? Oops, you've rsynced the new version and lost the old.
That said, I do prefer hard drives as a backup medium, over tape. I use the same tar files (full, incrementals), just put them on the hard disk. Further, we'll burn snapshots of really important stuff (e.g. CVS tree) to CDR.
And yes, offsite backup is a must.
I have dozens of audio CD-Rs in my car, all from generic spindlepacks, burned on a mish-mash of writers at 4x that are still going strong in spite being frozen/thawed all winter long (MN winters, frequent temps below 20 F), baked in the sun in the summer (I have the cheapo ramp spot on the roof deck, avg daily in-car temp ~120F), jammed into and out of the visor CD holder, chucked in the floor, and all other kinds of manhandling.
I did have some Kodak CD-Rs in '98 that crapped out on me; the dye appeared to fade over time and ultimately they became unreadable. Dunno what the deal was.
I do notice that CD-Rs burned at 8x (on a 8x max burner) tend to skip more than CD-Rs burned at 4x on the same burner. Does the dye "burn" better at slower speeds?
Ask them what they use for backups? (And they want to swap some p0rn.)
I know some people are too stupid to read a post and react to it all by themselves. That's why we have the moderation categories (Insightful, funny, etc).
Sometimes a post will get moderated with the wrong label, and this just leads to confusion.
To clear the record, the offending post should have been moderated "Funny" (partly because of the pornography related joke, and partly because of the rest of the joke).
I hope this clears things up.
the temperature being a factor, I think it's minor compared to the dye used.
:)
when CDs were first available, your typical colours/lifespans were:
green - approx 1 year
blue - 2-5 years
gold - 20 years
silver (pressed) - lifetime
I think that was the lifespans. nowadays, dyes are mixed. I always used to buy gold CDs even though they were more expensive. I was burning porn on them, and didn't want to lose it all
I can still read discs from 97-98, and it's most likely because of the quality of the discs. It's certainly a different CD Rom. I've changed computers a million times since then. I've not really taken much notice of temperature, although I've kept them out of direct sunlight, and I haven't really taken overly good care of them. They've been well used and lent out to heaps of people.
The reason girls and Windows users don't understand UNIX is because all the documentation is in Man files.
Wouldn't it be ironic if the only disks that last 15 years are old AOL disks?
Imagine being an archeologist after WW3 who keeps digging around looking for CD's on various topics, only to find tons of AOL disks that still work.
Table-ized A.I.
I've talked to companies which make these types of tools and asked the same question. The simple answer is that a normal CDRom is just not built for advanced testing. Testing drives have specific hardware to detect errors that a normal CD can't. Naturally these errors don't influence the percieved quality of the product, since they can't be measured by standard hardware. However it can demonstrate problems with the manufacturing process.
It has to do with how well the foil is attached to the back of the cdr. When it falls off, all bets are over. It has nothing to do with how accuratly the data is written on the cd.
I know the feeling. Though if the person is bottom posting and hasn't snipped stuff in the text then his/her opinion is probably not worth much in any case. ;-)
Though I don't really care. I prefer it the way it is on eg Slashdot where you have to make an effort to actually quote stuff. Keeps the noise down a lot.
I have around 600 cd-r's sitting in my room many of them going back 48 months+ (4 years for the less gifted)...
The simple answer is that a normal CDRom is just not built for advanced testing.
I agree with that. I don't expect functionality equivalent to specialized hardware. I just want to do as much as possible with standard hardware. A standard CD-ROM drive will read some raw data from media and then do error-correction. The error-correction is probably done with a combination of specialized hardware and some firmware code. I just want the drive to skip this step and send me the raw data from the disc in whatever format it is. An identical error-correction step could then be performed in software, though it would probably be slower. But you get the chance to know how many bits was actually changed by the error-correction, and you can apply more advanced algorithms to do the error-correction if the normal one fails.
Do you care about the security of your wireless mouse?
Well if TDK and other big brands are enforcing quality standards it may not be so bad. I can't help but wonder if big brands farm out manufacturing, test, and rejects may be sold as generics if they were merely low quality rather than outright defects. Just speculation.
That syas if 50% of them fail in the 1st year, 50% of them could fail in year 20. I've got several drives that have been running for more than a decade.
on eBay when the riaa gets rid of the machines they confiscate from pirate shops. Make 10000 copies and store them somewhere. One of them has gotta work in 10 years time
i use the apple dvd-r media to do my storage / backup. aside from the increased capacity, the media is better constructed than any cd-r i've seen. the metal is sandwiched between 2 layers of plastic... cd's will be phased out soon enough (after all, burners can only get so fast, and software can only take up so many cd's...)
i *had* several panasonic phase change drives.
the media and technology is shit. period. it died off for good reason.
every single one of the discs died within a year with unrecoverable errors under even light occasional use.
even the crappiest CDR/RW technology I have seen is light years beyond that panasonic phase change crap.
ps i still have the drive and dead media sitting around, if anyone wants to buy it cheap...
I feel so disillusioned.
are they still readable?
yes or no.
For the ultimate backup use the Rosetta Disk. It sez that they can record up to 30,000 pages of text on a 3inch coin. Plain text toboot, no binary. It is actually pretty cool check it out.
In the end they will lay their freedom at our feet, and say to us, "Make us your slaves, but feed us." - Dostoevsky
There is one thing that unites ALL of us!!
We all read slashdot!
duh!
I have some old floppies from the 80s that are still readable, but nowadays this is my best practices for floppies: good enough to get a network or SCSI driver to a machine to get it up and running. If it has a CD drive, burn the drivers. If I don't have an extra monitor, key board, etc., and the main machive needs turned off, or if I only have one floppy drive handy, I make three copies, because the drives and disks suck so bad.
"The biggest benefit is that it cuts WAY down on the number of +5 posts, so you can get straight to the key comments if that's all you want."
Sorry that you have a 2x4 up your ass. If you pull it out, you can sit and relax for a change.
But hey, maybe you like it that way.
Given that you're instantly confining him to your foes list, the group list which you belong to must be "christian fundies".
Oh no, did I just get added to yor foes list too? OMFG! WTF!?! LOL!!
"I have some CDRs that stopped working within days and others that have lasted over 4 years now--same brand from the same spindle even."
Sounds to me like the difference is in the way you treat each CD. This has been the single largest factor, in my experience. Treat them with the most delicate care, and they will almost surely last *much* longer than if you keep dropping them face down whenever you get the chance.
Why does every porn joke get instantly rated "5, Funny"?
Because the reply was funny, so we had to mod up the parent as well!
If Google really cared they would fix Android Chrome to reflow text, instead of discriminating
After reading your profile, I stand corrected. *burns my feminist card*
Replacing the feminist card is not an option, atm, tho. :(
i was not linking to the main site, but to their 'feminist definitions' page, which i find to be accurate (strangly enough for the content main site).
MilkMiruku
You're joking, right? I hope you are. But if you aren't, then: If something catastrophic were to happen at my friend's house, then obviously I would still have all of my original data at home. Then I would leave a fresh backup at his new place, after helping him get settled in there.
Leaving a CD-R at a friend's house is free. Fireproof safes are not. In addition, what if the burglars were to find and steal that safe, hoping to be able to break it open at their leisure and get the valuables inside? Then you would be wishing you had a current backup off-site.
From the looks of the broken pieces, it seems that the CD-R is just a plastic disc with the label applied on top doubling as the writing surface, ie, when i peeled the top off the a plastic disc piece, the shiny surface that the laser burns into peeled away as well. And it was VERY thin.
Apart from one critical time when I simply ran out of storage capacity and had my only copy of something on a Zip disk, I've never lost a peice of data that I didn't purposely delete. I never have my only copy of anything I care about on a single CD. I used to have CD backup copies and an archive hard disk. The hard disk got re-tasked, so I made a second copy of its contents. I am currently re-creating the old archive drive plus all the data I've accumulated since its time on a new hard drive, and some of the CDs aren't working properly after only four or five years. When I've finished organising the archive I'll probably burn it to DVD. In a number of years I'll look at migrating it to the next medium...
Some would say dating Natalie Portman WOULD BE heaven! :^)
On the topic, I'm scared. I've been backing up
important stuff to CD-R for about a year and a
half (I was late joining the party, okay). What
am I going to do now? I'm serious, help me!!!
"This is shocking, and makes me wonder how should I backup my data, photo and music collection."
Simpley put: Don't do backups on CD-R. You should be ashamed to backup like a little boy who backed his Atari ST's 120MB HDD to floppy-disks, coz' he could not afford the rest.
There is options:
a) S-ATA HDAs in HotSwap frames
b) DDS (unreliable)
c) ADR Onstream
d) there is plenty of tapes, not all suitable for consumers, however
They get paid for their shoots, do they not? No one exploited there.
What is exploitive is strip clubs. They aren't exploitive to women, they are exploitive to men.
Someone, somewhere, suggested burning at least
two copies of the information you want to save,
and with media so cheap, I've been doing that.
I think that that will at least increase my odds.
But I agree with you, buying better quality media,
at a premium, would be the safest way.
Face it; the attention span of the majority is about 3 seconds, so it is funny to them. Also, "funny" is very subjective, so you stand a great chance of getting metamoterated as unfair had you done so (assuming metamoderation applies to all moderation types).
:o)
Not that I disagree with your assessment of how funny it was... it certianly wasn't "laugh out loud" funny.
--
Me spell chucker work grate. Need grandma chicken.
How can you possibly have a userid that indicates you've been reading slashdot since the start (even if it were fitfully) and be in any way surprised by this?
Yeah you're right, no huge surprise. Just a bit of a disgusted rant.
Also, "funny" is very subjective, so you stand a great chance of getting metamoterated as unfair had you done so (assuming metamoderation applies to all moderation types).
I could be wrong, but I think Overrated and Underrated are not metamoderated.
It actually depends on the drive. I remember back in the day when Adaptec Easy CD Creator put out a regular newsletter and discussed this. The older drives would produce less crc errors at slow speeds. Newer high speed drives will do better at high speeds because that is what they are designed for. The higher speed drives are only calibrated at the top speed burns.
BTW, I had some audio cds stored in my car that lasted over 5 years. I finally threw 'em out because they started skipping on some tracks. I still have some data backup discs from the same time perios and they still work fine. Of course they are stored in a less environmentally extreme storage- in the cabinet above my desk.
Just a Tuna in the Sea of Life
The page you pointed to implies that the discs could last up to 200 years. I don't see anywhere that they guarantee it.
You think you've got worries, I've been backing up for over 5 years.
I haven't lost a single file to my knowledge though.
BTW, 200 year discs mean squat if you do not store them properly. Though they can still last a relatively long time. I had some audio discs last about 5 years stored in the car.
Just a Tuna in the Sea of Life
(unless you have a case of those little bugs that like eating the data layer)
Those aren't bugs, those are features..
*duck*
I thought error correction was done by the
CD player itself (hardware). Would you not
need special hardware to test the CDs --
hardware that gave you the 'raw' as opposed
to error-corrected data?
The parent points to a software product.
This makes no sense to me. If I am off,
please enlighten me!
It seems to me that something along these lines should be standard fare when it comes to backing up to CD-Rs. As others have already suggested: MAKE SEVERAL COPIES.
Does anyone know where to buy gold CD-Rs? Kodak has stopped making them.
This is pretty much what I do. I have a file server with the 1 OS drive (to boot and run from, obviously), 1 NFS export drive (for all of my important data), 1 drive that mirrors the previous drive, and 1 more drive to hold backups of the
This solution has worked like a charm for me. The real workhorse is rdiff-backup, which when thrown into a crontab, does automatic daily incremental backups of everything mentioned above without any intervention at all. Quick tip: you can use hdparm in Linux to literally turn off drives that are only used once a day to help save some wear and tear on them, plus electricity.
Hey, sorry for my previous comment. I've been having a bad day and making that type of remark is normally uncharacteristic of me.
Experts agree: everything is fine.
what i need is a place where it isn't since everywhere someone is trying to use it for profit (eg.: tv) or attention (eg.: "funny" jokes). And what i *love* is my girlfriend.
Too true, works for me. :)
Either that or I just emulate whatever with VMWare until I've got enough scratch for another personal machine.
Dating would just allow you to be seen with Natalie Portman in public, making your fellow geek friends quite envious.
***
Radio Shack. You've got questions...we've got blank stares(TM).
Nah, I've seen some of the really really dark blue stuff around, although it was years and years ago. No clue if they're currently still existing or what condition they're in, but I know they existed at one point of time. I don't remember having any problems w/ 'em.
;)
Not much help I realize, but posting takes 10 seconds and is cheap.
I don't have any real experience to report about long-term readibility, but I've had a client leave a spindle of Memorex CR-R's in a sunlit window for a while, after which about 30% of 'em weren't *writable*.
What the hell, there has to be *some* way to blame the RIAA for this, anyway, right?
Floppies. Lots and lots of floppies. ;P
I remember when CDs first came out they were touted as being able to "last forever," but for those of us that have a couple hundred CDs in our cars, we've inevitably thrown a CD down and contributed to its shortened lifespan. If there were a cover, this wouldn't be a problem.
I wonder if the **IAs had some say in the matter. Planned obsolescence is good for business, after all.
***
Radio Shack. You've got questions...we've got blank stares(TM).
"Not I", said the fly!!
"I didn't come here to tell you how this is going to end. I came here to tell you how it's going to begin"
> Since Slashdot certainly has its share of political left, right, and women, it's easy to see that no one thing will EVER unite ALL Slashdot readers.
Sure there is. Our love of bandwidth.
if the answer isn't violence, neither is your silence / freedom of expression doesn't make it alright
This is shocking, and makes me wonder how should I backup my data, photo and music collection.
On 9 track tape. The very idea might be funny to some but 9 track tape was superbly secure.
I'm a 26 year old male who finds a lot of pornography offensive. Especially spam that's trying to sell it. The implication is that I'm some desperate sob who would actually pay for it. Heh, they'd have to pay me to bother to look at that crap. I have better things to do with my time, like hang out w/my gf.
Older Yamaha drives were notorious for overheating and dying in record numbers. I'd bet that all of your 19 drives were mounted internally without adequate airflow or ventilation.
I've purchased 3 external Yamaha drives since 97, and to date they are all still working perfectly well; alebit very slowly.
Personally, I feel how one stores their media after they've been written is much more important. Things like humidity, range of temperature affect the life and stability of the media.
get retrospect backup software. i pirated it but i would buy it if it wasnt thousands of dollars...
:)
/scsi /firewire /sata /ata /usb2 this thing has you covered.
its amazing backup software though, maybe this review earns me a free copy
i have about 200gb and 150gb of storage so i bakcup. it has good compression over multiple drives and is easy as anything to restore.. fast and reliable to anything from
had to search google for a s/n
Speed does make a difference, but slower is definitely NOT neccesarily better. Writing at 1x in a 48x burner guarantees you the worst quality you'll be able to get. Both drive and media were designed for much higher speeds.
For example, this article contains a nice analysis from the 12x days.
Also, don't be confused by pits: The LENGTH of the pit is the data. The pit can be 3 to 11 um long, and encodes 3 bits (8 values) into a single pit. The space between the pits doesn't matter much, it just cannot be too large because the laser has to have pits in order to follow the spiral.
Musicians don't die. They just decompose.
I'm also concerned that whenever I eject a CD/DVD, the disc is quite warm. It's especially true if you have avi files or a movie that is in a drive for around 2 hours (more so with avi files on a DVD-/+R).
That's great... for you. Tapes are, I think, generally more reliable than CDRs over the long haul, if you use a new, high quality tape in a clean, properly aligned drive. But tapes pose their own set of problems.
1> The favorite tape formfactor has changed several times in the consumer side of the business, and at least once or twice in the business side. You may not be able to find a drive that plays your tapes ten years from now, at least without a lot of trouble.
2> If you still have your old tape drive, it may well have worn out, broken down, or simply fallen out of adjustment. Tape drives are very fussy things.
3> Tape drives, being very mechanical, are fussy things to begin with. If you want to be sure you can read that data in 10 years, better double check it in at least one other drive today.
4> Tapes wear out. After spooling them back and forth a few thousand times, they just don't work like they used to. IIRC CDRWs do too, so be carefull out there.
5> Tapes don't have a fraction of the installed base of CD-ROMS.
6> Tapes are remain vulnerable to the elements. Not as much to light, but the binder can give out and the tape start flaking. If the drive misfeeds, the tape can get tangled, threatening your data. If you get the tape too near something magnetic, it threatens data integrity, in audio tape you can even get print-tough after a while, where loops of tape affect the contents of their neighbors.
So tapes have their place, but they are hardly the panacea you suggest.
And hard-drive backups? The hard drives I've bought in the last couple years seem to have a MTBF of 18 months. Be careful out there and be sure you know the limits of your media
I read in the past that CD-Rs have a finite shelf life and need to be written to before a year or so of manufacture date. Urban legend?
Sorry, I misread your comment. I will pay more attention next time :-)
-- Cheers!
You should get your friend to copy each CDRW you give him onto his computer, so that you know that the backup really is a backup and not a decorative ornament.
What I do is live in two places and every time I go from A to B or B to A, my entire life is burned onto CDR and CDRW (ie two backups) and reloaded at the other place. That way I'll know at once if a backup is unreadable.
When I was between 14 and 18 (1988 to 1992) I made a tidy profit from aligning 1541 and 1571 drives. I had a small army of surgically aligned disks made from perfectly aligned mechanisms tested by oscilloscope, and an alignment program I found on a local BBS.
I still have all of them, however having been in storage for so long, I question the quality of the disks. Talking about CD-R media quality, I have a number of Verbatim, TDK, StorageMaster 5-1/4" floppies that are STILL in readable condition after 14+ years. I'm in the process of using my Amiga's 5-1/4" drive to archive them all in expectation of failure.
Line you raid case in lead too, keep out them stray cosimc rays too. Can't hurt.
Pah, 56k ought to be enough for anybody who's not doing anything illegal or immoral.
Now if you'll excuse me, Jenna Jameson just finished downloading.
You are right, the fire will only destroy the left side of everything in the house, so if I keep one side of the mirror on the left and the other side on the right, everything will be OK. Tell us you are not in charge of disaster recovery?
I certainly don't want to go to the lengths of making an active "hot site" to replace my home computer room, but home fires are not out of the ordinary.
"Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
(EOM)
i have some audio CDs that I made in 1997 burned at 2x. well actually a guy down the hall at school (the only one with a burner) made them for me, and now every player i put them in skips like crazy.
might just be burning technology in its infancy, but i'd say this estimation is right on. maybe not within 2 years, but within 5 i wouldn't trust burned audio CDs. although some DATA CDs burned on SONY disks at 4x (forget the brand of the burner) made in 1998 still appear to be doing well...
Can't beat ceramics. How old are the clay tablets in IRAQ? I have been told (totally unverified) that people have been able to play back sound from the trim lines on ceramic pots. The idea being that when they dug the metal tool into the soft clay body on a wheel they transferred some vibrations into the groove. I'm sure you would have to correct for pitch (ceramics shrink in the kiln.) A small enough particle size and a slow enough firing technique and you could make some LP's that would outlast almost any other media. Hell they'd outlast the English language.
If Wired Mag was right last month and diamonds are now on the cheap we might get some nice CD's made from a diamond platter with Platinum wire. I'm guessing that would last a LONG time.
If not buy 30 different types of CD's and burn em all. If you data is really that important the extra effort can't be that great.
Buy a "Foodsaver" and vacuum seal all you data and throw it in a dark freezer. Oxygen and light break more things than you might imagine.
Doesn't this all stink of the long now society?
I don't know what the article is talking about. I *personally* have several CD-R discs from 1996 or so and apart from mechanical damage (scratches, peeling, etc caused by abuse) all are still readable. I don't have too many hard drives from that era that still work.
It's simply logical. A hard drive is a complex, precision-made instrument that spins at very high speeds and has extremely high storage density on delicate metal platters. A CD-R disc is a stamped piece of plastic with a dye layer on top. It has low storage density, and is not subjected to heat or high speeds. Store the CD-R in its case (or, better yet, a caddy) in a climate-controlled environment, and it will last for decades.
Supposedly these bacteria are only an issue in tropical climates. My family is from the caribbean and I have seen this one Princo disc burned by my uncle that was being eaten on the inside by this stuff. It was gross. Fortunately for me I now live in the great white frozen North that is Canada ;-)
Not really. Hard drives generally fail due to either mechanical damage that IS caused by use, or -- more commonly -- bad clusters, which can be caused by anything from manufacturing defects to temperature changes.
This answers one part of the question, but I burn 4x and 16x CD-Rs at 4x with a continued zero failure rate over several years. I refuse to upgrade or change brands (external usb hp burner, Memorex (yes I know) disks) because they've worked so well while people I know have nightmares with all kinds of other combinations of better and worse brands of both.
---
When I grow up, I want to be a kid again.
Riiight. Pictures of tentacles in erotic positions -- no way.
Ummmm. Is that supposed to be green?
"-1 Troll" is the apparently the same as "-1 I disagree with you."
You've never seen a case of CD-R eating fungus. Supposedly it is only an issue in tropical climates. I've seen it on a disc burned in the Caribbean.
Umm, yeah right. I was replying to someone who was suggesting backing up data to a hard disk. I simply suggested a way of making this simpler in some cases. I was not suggesting a general backup solution so I not really sure what you are on about when you say "Tell us you are not in charge of disaster recovery".
Actually, it IS an overheating issue, and it doesn't matter if the drive is well-ventilated or not, because the part that overheats is the Yamaha CDRW *itself* -- it's HOT any time it's powered on. Hence the drive's life can be measured in total system uptime, that being about 9 months if the system runs 24/7. In a box that spends most of its life turned off, the drive will last a bit longer (longest known to date is just over 2 years, in a system that only runs occasionally).
An early sign of drive failure is that the CDRW will write two CDs okay, then #3 is a coaster. Turn it off and let it get dead-cold, rinse and repeat.
Apparently what happens is that the drive head heat-warps, and over time it gets more and more out of alignment. SCSI and IDE are equally affected (having dismangled one of each, I learned that they're identical internally). 4x tended to last slightly longer than 6x or 8x -- the average 4x at least made it out of warranty. I don't know of a single 6x or 8x that didn't have signs of failure before hitting one year old.
I detailed my observations to Yamaha tech support, and what I got for my trouble was "Thanks, good info".
And frankly, no one has any business designing a component that is so heat-sensitive (or that generates so much excess heat, as is the case here) that it can't be installed on an average system. My boxes run fairly cool, being much better-ventilated than most (with extra internal and external fans), and I still had the problem with 3 Yahama drives of my own.
Indeed, I'd expect that external drives, having more direct heat loss thru the external case, would last longer. But are they powered up 24/7? Try that, and see how long they last. You might be in for a rude surprise.
Anyway, when I heard Yamaha was getting out of the CDRW business, my response was "good riddance". I now have a Plextor and two LiteOns.
~REZ~ #43301. Who'd fake being me anyway?
Most of my cheap CD-R's burned in 2000 are unreadable now. Probably going to have to transfer them to DVD-R.
I use Goldenhawk Technology's CDR-Win, which, while it doesn't have the most intuitive interface, does seem to offer a lot of functionality. It has an option to verify the cd.
FWIW, over the last week or two I've copied about 300 CD-Rs onto disk that were recorded in the 1998 to 2001 timeframe, and the only real problem I saw was with one that was visibly scratched. I recorded them all at 4x.
Well, typicaly when aliens invade the Moon, sooner or later Heather Lelache will suggest to George Orr to "do something about those aliens on the moon" when she is hypnotizing him before sleep.
while i have had very good luck, if that is the status, in CDR recording and playback, i do make more than just one CDR backup... there is safety in numbers! also, i am coming to the conclusion that i must agree with a thread which i believe i found on another site, (was it =>ExtremeTech.com?) in which the author suggested backing up to a new HDD in addition to any other removable media CDR, tape, etc. each generation HDD seems to have so much more capacity... i wonder, why not just do a save of all your data into a folder or directory on a cheap spare hard drive... (\YR2003 for instance) and be done with the rest until you upgrade again.
So, yes, greed^Hn is good, but dark blue is *much* better.
I just tried and the answer is YES and NO.
They are still readable in my PC's CDROM
but not in the DVD player (which was able to
successfully play them before).
so long as entropy exists, so will bitrot, and the finer you pack-em, the more ephemeral they'll become.
experiential memory will outlast data.
Taking it down every backup - fair point, hot swap bays would be worth it on an important server though, surely, and if it's nto that important, then taking it down every so often isn't the end of the world? Clearly it may not always be the best thing, but better than built in hard drives.
Two full sets, yes, I think people here are suggesting you migh want to keep a stack of past drive archives anyway.
Clearly they can't be swapped too often, does that count for the mounting or just the drive itself? The drive isn't an issue, you only need to swap it a couple of times. Mounting is more of a problem.
I have newer drives that won't let me burn at anything less than 4x (don't know why), and they give me less reliable recordings than I got when I burned at 1x. I'm talking about audio recordings here, disks that are treated very carefully - never a scratch - and after the first 60 minutes they get very flaky, even on the first playing. They stop, they hesitate, they are useless. They are supposed to be 80 minute CDs. Maybe I should just avoid Sony and Memorex CD-Rs, I never had a problem with Imation ...
"A generation which ignores history has no past and no future." -- Robert Heinlein
But if you're doing simple shared backup with another company, you're their backup and they're yours, and that's fine as long as you both can risk having your remote backup site down for a day. Obviously you both need to have internet bandwidth that's adequate for the amount of data you're backing up, plus the amount you need for regular traffic, so it may or may not be cost-effective compared to having your sysadmin take home one disk from a raid mirror every night, but you can certainly back up really critical things like your accounts receivable ledger and nightly build data and the logs from your incoming email.
Encryption isn't that hard - you always send the files to the backup site encrypted, and keep the private keys in your bank safe deposit box (or three halves of them in three separate boxes.)
Internet load depends a lot on how much you're really backing up, and how much needs to be backed up instantaneously vs. overnight. In some ways it helps to have the same ISP for both sites, and preferably in the same city, but if you've got different ISPs, it's nicer if they have peering within a few hundred miles of where you are. If your backups don't have to be too tightly synchronized, you can use a dirt-cheap ISP, figuring that even if they can't provide you peak bandwidth 24 hours a day, getting 90% of your bandwidth 18 hours a day is good enough for many backup situations.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
I'm pretty sure Ricoh is Japanese, and is one of the better media manufacturers.
Japanese manufacturers:
MCC (Mitsubishi Chemical Corp.) - Verbatim discs used to be MCC. They are now CMC Mag (see below)
Taiyo Yuden
(I believe) Maxell - Beware of counterfeit Maxell media
Sony
TDK - Their "Armor Plated" DVDs are regarded as the best DVD-R media in existence. Of course, it is also the most expensive... Even more expensive than Pioneer-branded media.
A few others
Taiwanese manufacturers:
CMC Magnetics (suck) - Can be found as KHypermedia, OptimumDisc, Memorex, and now Verbatim (i.e. Verbatim used to sell great media, but I would avoid them from now on.)
Princo (ultra-suck)
Ritek (Best of the Taiwanese manufacturers, rivaling the Japanese for quality. Riteks are the best "bang for your buck" for DVD-Rs.)
Optodisc (ultra-suck, at least their DVD-RW discs)
retrorocket.o not found, launch anyway?
My first CD-R drive was a Panasonic CW-7502B - 4x8 -R only.
:(
I have NEVEr had a corrupt burn with it and much of the media burned with that drive is still working today.
On the other hand, stuff I burned at 32-48x in my LiteOn is a crapshoot - I have a number of HP-branded discs that are beginning to die after 2 years. It can be partially blamed on the storage, I was using a CD case that wound up leaving deposits on the disc.
retrorocket.o not found, launch anyway?
Cool! I guess I'll have to go out and grab some of the dark dark blue CDs. I've seen a few of them around work... I wonder where they came from...
My first writer was 2x (first reader 1x). But that's not to say the writer still works; it quickly lost the ability to write to CDRW's and only would make "readable" CDRs at 1x after a while. Hardly the drive I would want to trust to write long term storage discs. So the point still stands, there was advice that if you want to preserve data the longest write at 1x, but I know of no available equipment that will do that. Is 4 4x good enough? Heck, it sounds like 1x isn't good enough, I would hate to save stuff at 4x based on just your hunch. But I haven't been able to find any real since about the article, such as brands tested, speeds used and so on. It's a very ancidotal story at this point, was hardly worth posting if there is no data to back it up.
I'm an American. I love this country and the freedoms that we used to have.
Well, the problem in your case was that you were using an early generation drive. The average CD-R drive sucked until the era of 4x CD-R drives. (Back when the Panasonic/Matsushita CW-7502B came out, people soon regarded it as one of the most reliable CD-R drives out there. So far with the exception of massive media damage, everything burned at 4x in my old 7502 is still working well.)
Back in the days when CD-R was new and 2x was blazingly fast, CD-R recording was even more of a crapshoot than DVD recording is now.
Things are different. 4x on a modern drive capable of 48x is going to be FAR more reliable than 1x on an crappy early-gen drive that was only specced at 2x. CD recording is a mature technology now. It will (of course) depend on the drive you use. 4x in a recent Lite-On or Plextor should last forever for you.
retrorocket.o not found, launch anyway?
700th Post!
Again, just a hunch with no test data to support it.
I'm an American. I love this country and the freedoms that we used to have.
The application which will have a problem with the short life found for CD-Rs is not backup, but archival storage.
Eg, where will you store your digital photos? For that kind of ordinary, real world application we need a medium with a life measured in at least decades, preferably centuries.
You buy certified archival media instead of whatever the cheapest CD-R media in the store is.
There is CD-R media out there certified by independant testing organizations to have a 25 year shelf life. It does cost a hair more per disk than the super-cheap disks at Wal*Mart though.
Happy Fun Ball is for external use only.
"Again, just a hunch with no test data to support it."
I can confirm that discs burned at 4x in my Lite-On have lasted FAR longer than discs burned at 48x, some of which are exhibiting data corruption even after 5-6 months, and also had initially better burn quality. (I have never once had a read error from a disc burned at 4x that wasn't severely scratched, while I've had read errors from day 1 on discs burned at full speed, or even down at 24x on 48x rated media.)
It seems like YOU are the one with no test data to support your claims, other than bad experiences with a POS first-generation drive.
retrorocket.o not found, launch anyway?
What if the building catches fire?
What if you need a version of the spreadsheet from before you posted last quarter's results?
What about data you are required to retain for a certain period of time?
Real backup includes placing data offsite and retaining periodic snapshots of your data at a given point in time.
This is why most real business backup systems involve tape at some point. You can put tapes in a library for automated media changing. Tapes are easy to periodicly send off site. Tapes have a known maximum shelf life for reliably retaining data.
Happy Fun Ball is for external use only.
we literally dropped this system in place of our old DDS drives and never looked back. makes recovery a snap as i can just pop the drive into any old machine and its ready to go!
DDS? how passe. Real men use LTO or IBM cartriges in a autochanger.
Happy Fun Ball is for external use only.
Indeed maybe the problem doesn't lie with the recordable media, but the Hardware used to burn it during said test on 30 different kinds of media.
/^([Ss]ame [Bb]at (time, |channel.)){2}$/
There were some cut-rate CD-R manufacturers in the late 90's that made discs with no top protective layer...It's pretty obvious whether the disc has it or not, simply look at the edge of the disc.
AFAIK, no mainstream manufacturer sold discs like this. And I haven't seen any in a long time, even cheapo discs have the protective layer nowadays.
A friend had some and I scratched off the layer with a sharpie. Whee!
I haven't seen discs like this in a while now.