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What Makes a Good CD/DVD Duplicator?
zachjb asks: "With all of the recent articles and buzz in the technology community regarding recordable/pressed optical disks being an unreliable medium to backup your data on, I figured the best way to keep my data alive is to duplicate my CDs/DVDs every few years. I've searched Froogle for CD/DVD duplicators, but I have no idea what I should be looking for. Does anyone in the Slashdot community have a lot experience with this type of equipment? Is this a reasonable solution to the problem or is there a more cost effective one?"
Personally, I think the best long term storage for a Slashdot reader would to be to build a home RAID server. Hard drives fail, but they rarely fail all at once. That's why a designed-for-redundancy RAID is perfect for this situation.
You don't really need to be concerned about hot-swapping, because you can afford your pictures being unavailable for the hour or so while you're swapping out a failed HD every few years.
I don't trust offline storage - bitrot is real.
I've decided that I'm going to keep all my data in online storage - the hard drives in my server. It's backed up (to an external USB2 hard drive) and I'm not going to lose it or find that I can't read it in five years.
Drive storage is cheap, simple and it works.
In fact, I think a set-top style box (though still a rather big one, at least now) could be built to do exactly what consumers need. And with increasing Internet bandwidths, it would be really cool if you could buy a movie with your remote control and have it delivered and stored on your system at home. If only the big few could get past their DRM-inducing fears and offer a reasonable way for consumers to do this. I believe that if this were offered with music, back when the whole Napster thing started, downloading stuff for free might have been a fringe weird geek sort of activity, because most reasonable people would have an easy way to get perfect recordings every time for a small payment. Hopefully the movie industry won't be so blind to this gaping wide business opportunity as to cause themselves the same problem, and eventually ruin technology for everyone by making it decide what we are and aren't allowed to do.
I had a former roommate who brought a nice but flea infested leather couch into my house.
My legs are crack for fleas.
Before calling an exterminator, I flea bombed the house with those flea/insect foggers. Several CDs that I left out were covered in a haze that made them unusable. The purchased audio CDs did not have the printed surface compromised but the silver computer CD-ROMs had the silver peel off.
I was able to use chrome polish (Welon) and a towel to restore the Music CDs so I could rip them but the Burned CDs were gone for good.
Be warned if you ever flea bomb your house and leave CDs out. And be careful with your choice of roommates.
- Zav - Imagine a Beowulf cluster of insensitive clods...
Snapshot This!
A snapshot is a freeze-frame image of your computer's hard drive. The location and contents of every file are noted in an instant, and then the computer continues with its work. Making a snapshot is like making an instant backup of the hard disk to the same drive.
Not every operating system supports snapshots, but the feature is becoming more popular. It was recently introduced in FreeBSD 5.0, for instance, although it wasn't really reliable until the 5.2 version. Snapshots have been a part of NetApp's gFiler appliances and EMC's storage systems for years.
The advantage of the snapshot is that it can be made very fast and it takes up hardly any disk space at all. That's because snapshots are implemented with a technique called "copy on write." Basically, the operating system makes a map that notes the name and contents of every file. If an application tries to overwrite one of these files after the snapshot is made, the operating system writes the new file contents to an unused location of the hard drive and preserves the original contents.
The same thing is done with directories. If you try to delete a file inside a directory, the computer actually writes a second directory onto the disk that doesn't have the file you just deleted. If you want to get back a file after you've accidentally deleted it, you just retrieve it from the snapshot.
On my primary server, for instance, I have a program that makes a snapshot every night at 11 p.m. I keep these snapshots for seven days, then they are automatically deleted.
The disadvantage of snapshots is that deleting a file doesn't actually free up space on the disk-the blocks remain "used" until every snapshot that references the file is deleted too. And, of course, snapshots don't protect you against a hardware failure or somebody accidentally formatting the hard drive.
One last thing: Once you have your backup system in place, you should practice trying to restore a backup from time-to-time. The best way to do this is to take a brand-new computer and a set of your backup tapes, and see if you can restore a 100 percent working system. Many organizations can't, so don't overlook this important test.
Copying from one drive to another on the fly like this can introduce lots of tiny errors. They're not that noticable, but the preferred method of getting an exact copy is to use something like EAC to extract to the hard drive first, then burn to CD.
"copy on write." Basically, the operating system makes a map that notes the name and contents of every file. If an application tries to overwrite one of these files after the snapshot is made, the operating system writes the new file contents to an unused location of the hard drive and preserves the original contents.
/source /somewhereElse/backup.0/
Rsync incremental does the same thing, with no special software or hardware.
Basically, it does
cp -al
This makes a ghost tree that is just hard links to the real tree. When a file is rsynced, rsync actually deletes and replaces the old file instead of changing the original file. This means you can use these hard links to track file revisions, and the idea is very similar to "copy-on-write".
The only drawback is that it isn't atomic, but most backup applications aren't that sensitive to a non-atomic backup operation anyway.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
I work for a business that duplicates CDs and DVDs. We have a bunch of autloading/burning/printing machines from companies like Primera. We can burn around 1500-2000 CDs daily. Mostly for places like banks or H&R Block. Anyways, www.primera.com has autoloaders and such available for purchase. Those machines work pretty well, although they take up quite a bit of the windows resources at work. I think they have mac compatible machines, but haven't checked in a while.
IMHO, it beats the pants off re-burning a huge stack of CD's every year, while praying that none of them turned out to have a lifetime of 364 days.
I made a PHP/MySQL library that prevents SQL injection & makes coding easier!
At my PSU campus our department has one of those multiple burner rigs. We use it to make CDs each semester for all enrolled CS students (under 200) and we make available (when asked) for copies of linux distributions (downloaded isos burned). The standard CDs include LaTeX programs, pdfs of handouts for all classes, and tons of other freeware (or we licensed it for the entire department cheaply) programs that students find helpful, like the ADA compilier used in the class.
This helps a lot for our students with only dialup at home as they can get easy access to software their peers can get in the dorms very quickly. It also ensures everyone is on a level playing field and no one can complain they didn't have the same access as another person.
Wheeeee
if it's data you need to archive but won't be accessing often, what about a simple solution such as an air-tight opaque box. without light or humidity, i would guess the discs would last much longer. after a certin point (x years), just bring up some handy disc copying software and copy for garunteed freshness!
No modern drive truely copies on the fly anymore. Remember the days when so much as moving your mouse could cause underrun errors that resulted in coasters? Those went away when burners got enough on-board cache memory to be able to not worry about running out of data unexpectedly, it'd be able to notice when it's buffer is about to run out with enough time to avoid making a coaster.
Likewise, the modern reader is smart enough not to return errant frames unless the error just happens to have also corrupted the CRC value and/or the math just happened to check. Not terribly likely, and if it did happen, the disc is likely already near-dead and not going to cooperate with copying anyway.
Burning from an HD image will usually turn out to be faster, but it's not going to be less error-prone.
People who regularly use insect sprays have the worst problems. The dried chemicals land on the fibers in the carpeting, and as they or their pets walk on the carpet their feet flick the toxic dust right back up into the air and into their lungs. Indoor air is now frequently more polluted than outdoor air.
Of course, you had a special case. You had a really, really stupid flea-infested roommate, and you used a flea-bomb one time to solve the problem. If it happens again, a good vacuuming immediately after the bombing and tossing out the bag when done would go a long way towards keeping your house healthy.
John
If the size of your cd archive is large enough, there will be a point that >=1 cd will fail everyday. Archive renewal will then be a continous process of checking/copying/discarding cds. It's better off to stay with more stable media than continously spending time/money on this IMO.
Because of the high prices of duplicators, and the fact that I would have liked to be able to just feed the machine a bunch of blank disks and a couple of spindles of used disks, with different instructions for each disk to be copied, I came up with an interesting plan. I'd post a link if I could handle the slashdot effect, but you might be able to find something similar.
Basically, the idea was to use a 4'x8' table, a mini-ITX case with a bunch of external drives (some readers, some burners, depending on your needs) and an Automation Direct PLC with serial communication capability to set up a "pick and place" type system that could easily be scripted. I lost my motivation before I had the $2k it probably would have taken me to do it, but the plan was pretty solid.
I think the motivation behind it was an interesting ice cream vending machine I saw, which was more or less a box containing a consumer freezer, an arm to open the freezer, and a vacuum hose that would go to the proper coordinates, drop down, suck up the treat, and drop it into a chute.
Just think of the possibilities though. Thousands of blanks, matched with thousands of sources. It'd make a nifty interface for archival and automated backups, etc.
I apparently forgot that sig != uptime...
That's not what hard links are... hard links are indistinguishable from the original file. If you make a hard link, modify the hard link then you'll see the changes in the "original" as well.
A copy on write snapshot does not change when you change the live version of the filesystem.
If you live in Australia (or fancy shipping a device weighing half a tonne from Oz,) you could try this
It's got a robotic arm to grab your discs from the top mug, chuck em in the burner, whack into the integrated printer and deliver to the bottom output mug, all fully networked so you can create jobs from another PC.
Every 6 months or so, I make a complete backup onto DVD-Rs. These days with 8x DVD-R burners and blank media going for $0.50, its just easier making backup copies onto DVD-Rs. Inbetween the 6 months, I backup if I have over 4.35gig of new stuff to backup and burn that.
That way you have a 'rotating' backup copy of your current items, as well as all your old backup copies.
RAID is a decent way to keep a systems FS up and running, but its no backup. I've had ATA cards and controlers take out whole HDD arrays.
Always backup, regardless...
Maybe I'm weird, but I find the HD a great backup medium. I don't have terabytes of shite I want to keep, but I do have about 80GB worth (slowly growing of course). This 80GB is made up of mostly iso images, movies, mp3s (mostly ripped, newer ones purchased from allofmp3.com), etc. It currently sits on a 120GB HD. When I bought this drive, I bought two. One for the stuff and one for the backup. Once every two weeks, a short cron job mounts the backup drive's partitions in /tmp, and throws rsync at the live stuff.
Now, this helps a lot with the "Jeesh I'm a dumbass" rm -rf scenario. If I don't remember within two weeks (or two days or whatever is left on the cycle) that I did a rm -rf on something I shouldn't have, well... Of course, if I did the rm -rf a few seconds before the cron job kicks off... OK... screwed.
When my 120GB drive gets close to full, I'll purchase two 200GB or two 280GB (or whatever) HDs and continue on. This has worked very well for me.
Oh yeah... If you set the backup drive to spin down, you'll feel good. hdparm is cool.
I am weird I guess.
3cx.org - A truly bad website.
I agree and that wouldn't mean much, were it not for the fact that I work with a publisher that produces book/CD sets and we turn out tens of thousands of CDs a year and we do them all by hand on standard CD burners using standard CD-R blanks. It's nowhere near as hard as it sounds. A thousand a week can be done with very little effort and since we have secretaries sitting around doing nothing most of the time, the labor is essentially free and they don't mind because it gives them an excuse to surf the net while they're changing disks. At one point we outsourced the copying, but it was apparent the company we outsourced to was just using CDRs, so we decided to do it ourselves for far, far less money. Outsourcing probably starts to make sense around ten thousand copies and at that point, you are probably doing quite well and not so worried about costs. But doing one at a time is indeed quite fast once you get started on several machines simultaneously.
Of course the downside to all this is that since we started adding CDs to our books, our sales have actually declined and the same is true for our competitors. It's easy to guess why, if it's so cheap and easy for us to make copies . . .
...to create a "WORM"-driver for a HDD. Like, it'd never delete anything by any normal file commands, store diffs for file changes, in general act almost like a WORM drive. Of course, if you're doing this "live" you'll have issues with files changing all the time. So simply configure it like:
For the last hour, keep all records.
For the last 24 hours, keep an hourly snapshot.
For the last week, keep a daily snapshot at midnight.
For the last 3 months, keep a weekly snapshot each Monday.
Basicly, it would work recursively to create the snapshot. If you're making a 1hr snapshot, combine all records of the last hour (i.e. if word auto-saved it 10 times, you get one "master diff". Same with 24h snapshot. Combine all the hourly ones. Changed it 8 times during the hours of a workday? It's now one daily diff.
Then you can simply have some "magic" functions like roll-back, cp -time "-4 hours" "mylostfile" "myrecoveredfile" etc. Given 100gb+ harddisks and 100kb word documents, umm I mean OpenOffice documents, why not?
Kjella
Live today, because you never know what tomorrow brings
I photograph graveyards using a Nikon D100 camera body, which on the medium quality setting produces 1.5-2MB JPG's. On a good day I'll shoot six to seven hundred images - 2 CD's worth. As I want these photos to survive my own death and someday be on file in the local historical society, I'm very concerned about their longevity.
Each night after I return from a photo expedition, I'll immediately copy the contents of the compact flash cards onto my Windows machine. They are stored there with a minimum of organization - just a directory named for the date. I then FTP them to the Linux machine, leaving a copy behind (plenty of disk space on the Windows machine).
On the Linux machine, on a 160GB disk that's used for almost nothing else, I'll sort the day's photos by location, putting them in subdirectories and adding a prefix to each filename based on the location (but leaving the image's original sequence number intact); this ensures that every file has a unique name even if the directories are munged together - something like "calvary/calvary7932.jpg"). I'll then group these directories together into lots of slightly under 650MB - depending on productivity, one day's work will fill either one or two CD's - write a text file as an index for each, and burn them.
My shell script wrapper for cdrecord will mount and list the contents of the disk after the burn is complete, allowing me to visually verify that it was successful. This has been useful, as on at least two occasions cdrecord recorded success but the disk would not mount.
At least five copies will be made of each, on different manufacturer's media, and stored in different locations. Currently, the media I'm using are Sony, Memorex, K-Hypermedia, Maxell Black, and Maxell Pro. These last are much more expensive but promise superior quality - time will tell if this is true.
The disks are stored in several locations - one copy of each into a sleeve in a binder, other copies storied upright in slim cases in various lightproof CD drawers in different rooms; a complete set is also at my parents' house in another city, and a friend in a nearby town will also be hosting a copy as soon as I drive out there with it.
I have a strict rule - no matter how tired I am, the Flash cards do not get erased until after I have written and verified at least one CD.
The images also remain on the 160GB drive in their original forms, and also in a parallel directory structure where everything has been resized (via shell scripts invoking gimp) to 600x400.
By next year I'll likely acquire a DVD-writer and make additional copies on DVD, again with the quintuple redundancy on different manufacturer's media. Five dollars isn't too much to spend to ensure the survival of a full day's work!
And a few years later, the process will be repeated with whatever replaces DVD's...
I bought the soundtrack to The Lord Of The Rings: The Return Of The King (2003) a while back to rip it with EAC to listen to it on my PC.
After loading the CD in the drive (suppresing autorun with the shift key) and accessing it resulted in it being perceived as a CD-ROM with files and not an audio disk with
Using Nero percieved the audio as
So I wound up making a
I wasn't sure this would work so I turned the volume down real low to avoid damaging/destroying the PC's speakers with static noise.
I was pleasantly surprised...it worked!
I then used RK Audio to compress the
Because of this, I've decide to use this process to archive/space shift my other music CDs with true, 100% fidelity an accuracy as this approach doesn't have the limitations that EAC has (and I have used it in the past and have been satisfied with its results back then).
PS: I'm eagerly waiting for the announced 9-CD release of music from The Lord Of The Rings movie trilogy (2001, 2002, 2003).
12 HOURS of music if (just about) everything (preferably everything) is included. Hopefully they won't screw up like what was done to the ultimate edition of The Phantom Menace (1999) soundtrack.
I don't buy this optical storage crap. They said my Commodore 64 5.25" floppies had a maximum life of ten years and that after that the data would be too corrupt to read. I just pulled out my C64 again a couple of years ago. Today, I put in my old Telengard disk from 1983 (haven't used it since about 1986-7) and damn if that bitch still loads! Granted, for my inner paranoid dillusional side, I do make duplicates, but the short lifespan we're hearing about with optical media sounds bogus to me. The only problem I have had with CD-Rs in the past ten years is the flaking off of the non-write side off the CD. That makes those suckers un-readable. To avoid that, just don't buy el-cheapo CD-Rs or if you do, put a label on the non-write side to help keep the surface from flaking off. OR, buy a decent name brand and you wont have to worry about it.
--I found a really nice CD duplicator at Target (brand name is E3WORKS) for about $200. Comes complete with USB 2.0 connection and audio-out.
Here's the exact model. It even works under Linux, as long as your kernel supports the right USB options.
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== WolfriderV6 == I'm willing to admit that *I just might* be wrong... Are you??
--I've got an e3works DiscClone; when duping, I always hit the "Standard speed" instead of the "Turbo". Accuracy is much more important than speed, IMHO.
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== WolfriderV6 == I'm willing to admit that *I just might* be wrong... Are you??