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Time to Purchase a DVD-R?
Evanrude asks: "With DVD writers having significantly come down in price over the past year more companies are coming out with their version of the DVD-R. My company has a large file archive of documents and data that don't necessarily need to be stored on read/write media, but need to be kept online. I want to accomplish this with online DVD storage but is this the right way to go? Who has the best value with the most features of all the DVD-R's on the market? What are some things to look for and things to avoid when purchasing a DVD-R? Is it even time to purchase one, or should I wait another six months?"
I've just been thinking the same thing. Unfortunately, there are a couple of competing standards out there now: DVD-RAM, DVD-RW and DVD+RW. The first, DVD-RAM, seems to have no future that I can see, and is apparantly a superclass for several different standards. Apple's DVD writers are the second kind and probably have the largest installed base. But it looks like the big players are going for the third ("+"). In addition, one of the -RW format's big supporters was Compaq and HP supports +RW. I'm assuming that Compaq will switch camps, leaving Apple more or less isolated. That has me leaning toward +RW.
One thing to watch out for -- the "first generation" of +RW drives can't handle write-once media. They're RW only, and the disks are more expensive. HP, for one, is releasing a second-generation writer (maybe called the 200i?) this month, that can do the write-once archival thing.
If I really needed it now, I'd go for a newer +RW format. But it would probably be less risky to wait 6-12 months to see how things shake out.
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DVD burners will go the same way as CD burners. There may be a bit more competition over formats (since it's a lot more obvious how much of a cash cow DVD burning is going to be for corporations), but eventually they will become fairly inexpensive. Give it at least six more months, if not a year or so, before you consider making DVD burners part of your company's storage strategy.
As someone once said, that's the great thing about standards, there are so many of them. You might want to wait and let the dust settle rather than risk a heavy investment in a possible orphan format. Already HP and a couple of other makers are weasling on drives that were supposed to be software upgradeable to record more than one DVD-R or RW format, but it turns out it's not going to be that simple and the hardware will have to be replaced.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
I work for a newspaper where we have just completed a cost comparison for CD based systems to DVD based systems. We have a large Image archive that was outgrowing our second 100 CD jukebox. Our quandry, should the new Jukebox be DVD or CD based.
4.1GB per disc (with double sided support not looking promising...) at 100 DVDs = 411 GB storage
100 CDs = 65GB storage. (roughly)
Our first look was at the costs associated. The Price difference between a DVD Jukebox and a CD jukebox was not insignificant, but was not a breaker. The writers have come down in price, and the Media is expensive, but not prohibitively so. So, from a simple cost perspective, the system was feasable.
However, when working with provided demo models, we found a 25% CHANCE OF BURNING A COASTER, with the write times being ridiculously slow. We then recalculated for the extra media expense and extended staffing. (The admin would need to keep a longer watch less often, but the CDs could be burned during the BU guys shift, now they will go past.)
With the addition of two hours employee time and planning for the purchase of 10% more media, the costs of DVD were slightly more. Then the vendor called, the DVD jukebox requires new switching Software that runs some $5,000.00.
So, we looked for used CD jukeboxes, found one for almost 1/2 the price of the hardware alone, and it still works with our old software.
Now, we did all of these calculations based on price per MB, and condidering the the DVD system has 7x the storage space, that also means it is 7x the cost. I feel confident that when we revisit this upgrade in 2 years the prices will be dramatically lower and the quality will be better. I still think you can't beat a $50 CDR and 0.20 media costs.
Unless you work for a company that enjoys having the latest and greatest (OOOH! I can access the SAN from my PocketPC with wireless.) I think you'd be better off sticking with the tried and true methods, wait for the writing SW to get more stable and wait for the standards to crystalize.
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Hammy
If you do go the DVD route, watch out for:
Running out of discs (these things go faster than you think)
Jammed discs
Depending on the client software, inane Windows error messages - quite a few programs don't know how to handle waiting for a disk to move into an active drive.
...and if you don't use Windows, well... lucky you. Just my experiences - everyone else's will undoubtedly vary.
You'll also need another DVD drive for each 5-10GB of data, if using DVD's
That's silly. A jukebox only requires one DVD drive for X number of DVDs, depending on your requirements X could be as large as 400 - that's the size of the largest consumer DVD *movie* jukebox - a Kenwood something or another.
As for data jukeboxes, take a look at the Powerfile C200 Studio which is $1000 MSRP (not street) for 200 DVDs. With blank DVDs runing about $1.25 in quantities of 100 that puts you at no more than $1250 for 940GB of online data and probably closer to $1K if you buy from a discount hardware place.
The equivalent space in hard disks is going to run you more than that - according to pricewatch, the cheapest 120GB is $136 for the IBM models. Ignoring the reliability questions regarding recent IBM hard disks, that puts you at about $1100 just for the drives alone, you are looking at another $500 or so for an IDE controller that will handle 8 drives (3ware escalade 7850) plus you then need some sort of case to hold the drives and the computer in one since IDE cables aren't suppossed to get much longer than 18".
So, at least $1700 for an equivalent disk-based system, without redundancy. The DVD approach will give you a full mirror in offline storage for another $250 but to put redundancy into the hard disk system you are going to need either raid-5 or mirroring - both of which will significantly push up the price because 8 drives is the limit for a 3ware controller so you could go with larger disks (160GB) but they are about 180% the price of the 120GB drives or you could go to two more controllers controller and maybe five 120GB drives per controller which is going to be another $500 for the 2nd controller and another $270 for the extra drives pushing the total up to $2500 or so for the cheapest raid-5 system.
Sure, online storage of a disk array is going to be a whole lot faster than near-line storage of a DVD jukebox, but the guy who asked the original question only needs near-line speeds and the price with DVDs is a about half that for sizes around 1TB.
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I had to take the plunge due to my having many GB's of digicam generated photos. My DLT backups were just using too many tapes.
Some random thoughts:
The second generation DVD+RW drives are just coming out. The only one availasble is the HP 200i. Here's an overview of the 2nd gen drives, and here's an overview of the 1st gen drives.
The 2nd generation drives support DVD+R, many of the 1st do not.
TheNerds.net have the best media prices. I looked a lot and could find no better.
The HP drive, which I bought, comes with "drive letter access" software. Basically, a packet writer so you can just use the Windows explorer (yes, where I use the drive) to drag and drop files onto it. I have the suspicion that my McAfee VirusScan 4.5.1 stopped working when I installed the HP software. McAfee has not been able to figure out why their software is not working (service error 5011, which is a timeout of some sort).
I've been trying to author some DVD's, and I had good luck playing my DVD+RW's in my DVD player. I used a trial of Uleads DVD Workshop.
I held off until the 2nd gen drives were available, and was forced to purchase the HP because it's the only one out. I would have prefered the Philips DVDRW228 over the HP, but no one has the Philips drive in stock, that I could find.
So far, I'm happy, and I'm hoping HP will update their drivers and VirusScan will start working again.
There are really three seperate categories you get into once you're considering moving data from primary storage. You seem to be asking about the first, but I'll cover all three for completeness.
Near-line (a.k.a secondary storage)
Primary storage almost always consists of the fastest hard drives directly attached to your data source (file server, SAN, workstation, whatever). Historically, near-line has been some medium where the end-user could access the data required in the same manner as primary storage, but at a slower rate. The old solution used to be either a different server using older/slower disks, or an RW optical jukebox. Near-line storage almost always is very high read-usage, but the occasional write isn't unlikely, so you generally want a media that can support writes.
Backups (a.k.a. save-your-ass storage)
Backups are a place to temporarily save data in case of an emergency. The criteria generally don't include re-writability, but do concern with ease-of-access in the case of a recovery. In addition, Backups expire - after a certain period of time, the data is no longer available. Tape has been the choice for this for a long time, with it's high storage capacity and low cost. Higher-end solutions have been the "on-line snapshot" capabilities of SAN and NAS devices (essentially to make a static mirror of data on extra storage space). CD-R and even floppies have been popular for the low-end. Whatever the choice is, the main concern is reliability, and the ability to backup the data within a set time window.
Archival (a.k.a save it for the history books)
This is a big one, and one frequently misunderstood. The two major criteria for Archival purposes are Survivability, and Retrievability. That is, the solution has to make sure it does NOT degrade with time (i.e. it doesn't introduce errors after sitting on the shelf for 20 years) and that you will realistically have a method to retrieve the data over it's lifetime (e.g. are they still going to have devices that can read your data media in 30 years?) Magnetic tape is a BAD THING for Archival purposes, despite its common usage. It fails on both tests. Mastered CDs (NOT CD-R) and Optical Disks are generally the preferred method here.
In the modern world, I would recommend a backup server using RAIDed IDE drives for Near-line these days. The relative cheapness of IDE drives, combined with the newer IDE RAID cards provides an unbeatable cost/storage/reliability ratio (far superior to CD, DVD, Tape, or Optical Disk), and it's by far the easiest to maintain and use, since it's simply another fileserver. Don't scrimp, however. A good one of these should probably run $3-$4k with 8-10 100GB drives, redundant power supply, and hardware RAID.
Backups are a bit more complex, and the variables make a one-size-fits-all recommendation unrealistic. And you didn't ask for that anyway, so I'm not going to make one. :-)
Archival really means you want to keep (or are required to keep) the data around, but don't need access to it much. If you don't intend to keep the data for more than 15-20 years, you can probably get away with CD-R. Otherwise, look into having your data pressed onto CD (i.e. real mastered CDs). They last a good 100 years or so, and it's relatively cheap. In either case, you want multiple copies of each disc, and the good-old CD-jukebox is your friend.
As you imply (and other posters have noted), DVD-R/RAM/RW/+RW isn't quite stabilized yet. Despite their larger capacity, I wouldn't change the above recommendations, other than replacing CDs with DVD when it settles down - DVD mastering isn't anywhere as cheap as CD mastering is (and if you do master DVDs, make sure that you specify UNENCRYPTED DVD so you don't get CSS put on accidentally).
As a side note: there's a whole industry built around Hierarchical Storage Management (HSM) which deals with automatically moving data between the various storage levels, and recovering it as need be. It's a bit beyond what you describe you're looking for, but look at one of the big UNIX storage players' (Sun, HP, IBM, EMC) site for a whitepaper on it. They're a good read for concepts which you can apply, even if you're not using their multi-million-dollar hardware/software packages.
Best of luck.
-Erik
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Hard drives on the other hand are very cost effective:
Under 1TB $1000-$1500
1-10 TB $4,500-$45,000 10+ TB $45,000+ Since you are looking at optical you are probably looking for a system in the 1 TB range. For this I would recommend a single UltraTrak. The purchase price will be a fraction of what a optical library would cost, the reliability will be better, and the maintenance will be cheaper. Maintenance of these things is very simple: when a drive fails the alarm goes off. Buy a new drive and put it in. That's it!Optical may not look that bad when you look at the purchase price and the idea of a robot is cool but you also have to look at the cost of maintaining a machine like that in terms of time and money. When you add it all up, hard drives win every time.
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