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Media Data Storage

How To Choose Archival CD/DVD Media 225

Posted by kdawson from the 70-years-or-bust dept.
An anonymous reader tips us to an article by Patrick McFarland, the well-known Free Software Magazine author, going into great detail on CD/DVD media. McFarland covers the history of these media from CDs through recordable DVDs, explaining the various formats and their strengths and drawbacks. The heart of the article is an essay on the DVD-R vs. DVD+R recording standards, leading to McFarland's recommendation for which media he buys for archival storage. Spoiler: it's Taiyo Yuden DVD+R all the way. From the article: "Unlike pressed CDs/DVDs, 'burnt' CDs/DVDs can eventually 'fade,' due to five things that affect the quality of CD media: sealing method, reflective layer, organic dye makeup, where it was manufactured, and your storage practices (please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media)."
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How To Choose Archival CD/DVD Media More

How To Choose Archival CD/DVD Media

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  • Moo (Score:5, Funny)

    by Chacham ( 981 ) on Monday December 11, 2006 @04:35PM (#17199248) Homepage Journal
    "Unlike pressed CDs/DVDs, 'burnt' CDs/DVDs can eventually 'fade,' due to five things that affect the quality of CD media: sealing method, reflective layer, organic dye makeup, where it was manufactured, and your storage practices (please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media)."

    How apropos.

    'slashdotters' can eventually fade due to five things that affect the quality of slashdot comments:

    • sealing method - The Sealing, in reality is the ceiling, and refers to the need to ceil() slashdot user's age to hit the double digits.
    • reflective layer - The Reflective layer is the use of low UIDs to represent importance of comments, rather than something actually informative.
    • organic dye makeup - Most comment's make up are so bad, they're DOA, and one can hear the organ playing.
    • where it was manufactured - There are no new comments on slashdot, everything is either culled from its dupe, or copied from the Microsoft Hater's handbook.
    • and your storage practices - Some comments are posted before they are fini

  • I'm Surprised (Score:3, Interesting)

    by aplusjimages ( 939458 ) on Monday December 11, 2006 @04:38PM (#17199286) Journal
    I'm surprised to hear that consumer media can last so long. I was under the impression that consumer media would only last at most 20 years. Good to know it is longer.

    • Patrick got his bits wrong... (Score:2, Informative)

      by Anonymous Coward

      This method is called 'pits and lands', where pits 'absorb' light (ie, are 'off' bits) and lands 'reflect' light (ie, are 'on' bits).
      This is incorrect - CDs record data using the transitions between light/dark and not the light/dark itself: see bottom of page http://www.digitalprosound.com/Features/2000/Sept/ RecCD2.htm [digitalprosound.com]

      • Re: (Score:2, Interesting)

        by dotgain ( 630123 )
        Well, if you're going to be that pedantic, the data still goes through an encoding layer called "Eight to fourteen modulation", which guarantees that a pit / land will be at least x bits and no more than y bits long, so the laser won't lose tracking due to not finding any transisions in a long time.
    • How do I actually buy TY disks? When I try there's so many counterfeits on the market that I don't know how to assure myself I am getting these. The problem gets far worse when one wants to minimize the price one pays so one is looking at on-line discount office supply companies without the reputation and high prices of the big chains.

    • Re:I'm Surprised (Score:5, Informative)

      by Anonymous Coward on Monday December 11, 2006 @07:34PM (#17201660)
      I'm surprised to hear that consumer media can last so long. I was under the impression that consumer media would only last at most 20 years. Good to know it is longer.

      All current forms of optical storage share the same problem that will limit their reliable life span. This problem will effect different media design types over different periods of time, but 20 years is a good average before you will start to see bit rot. How ever ALL optical media, regardless of being commercialy pressed or being consumer grade CD/DVD-R, will eventualy suffer bit rot for the exact same reasons. The problem is that the rate of expansion and contraction of the metal substrates that make up the innner layers and the plastics that make up the outter layers are very different. All optical media will suffer bit rot over time because of this, as what eventualy happens is the metal substrate inside the plastic protective layers gets warped and ripples start to form in the surface. This of course starts to alter the smooth/pit reflection encoding of data on the disc and ruins the data.

      Again, different types of optical media design will last longer than others. Yes, commercialy pressed CD/DVDs will last longer than consumer grade CD/DVD-R media on average. How ever none of these formats have the reliability and shelf life of magnetic backup tapes! Espeically newer formats like AIT, SAIT, and LTO (and VXA isn't too bad either, awesome pricing on smaller VXA auto loaders). So if you are looking for reliable long term archiving CD and DVD are NOT what you want to use! You want to use tapes. How ever, you can use CD or DVD if you keep in mind that this format has a shorter shelf life and you plan a migration of that data to a new removable media format say 10 years out from now. You have to do the same thing with tapes too, as eventualy formats become old enough that it gets hard to find tape drives that will read your backups. And yes there is still a limit to the shelf life of backup tapes, as over time the magnetic signals encoded in the tape start to transfer between layers due to the tape layers being tightly wound around each other on the take up spool. How ever, even with that in mind, tapes provide a much longer useful life span for archiving data. And beyond having a longer shelf life tapes have several other advantages. They have much larger capacities than CD/DVD media, so you don't have to sit there rotating tons of discs to restore a large archive. And in many cases newer tape formats have much faster transfer rates than CD/DVD (granted they cannot do random I/O, but burning CD/DVD isn't a random I/O process either). Any one who has serious data to protect shouldn't be using CD/DVD for backup. This is more of a cheap low end consumer approach for those who cannot dish out $1000+ for a good tape drive.

      Those who still have the wool pulled over theirs eyes and still think CD/DVDs are a long term storage platform need only look to those of us who have very old CDs and laser discs for proof to the contrary. I know plenty of people who bought some of the first pressings of CD albums back in the early 80s, and many of their earlier CDs are now suffering bit rot. This is even more prevelant on laser disc, probably because of the much larger surface area being affected. Many laser disc owners are fully aware of the problem of optical media bit rot. In many cases the bit rot gets bad enough that you can visualy see the distortions on the reflective surface.

      Bottom line, if you value your data then use backup tapes! That's what that technology was invented for! CD/DVD-R is more of a short term backup option, best for cheap short term archiving or transporting of data. I use CD/DVD-R for regular backups of the documents on some of my workstations. But when it comes to our servers and our customer's servers it's AIT or LTO tape drives all the way!! Use the right tool for the job!!

  • He forgot the most important one... (Score:5, Funny)

    by hal2814 ( 725639 ) on Monday December 11, 2006 @04:40PM (#17199328)
    "(please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media)." And NEVER ever feed them after midnight. On a more serious note, I used to worry about eventual degradation but it's coming up on 10 years that I've owned a CD-R drive and I have yet to run across a burned CD I cannot read due to this sort of degradation. Maybe at the decade mark, some of my discs will fail me and I'll change my mind but right now I'm not too concerned.

    • Re:He forgot the most important one... (Score:4, Informative)

      by Super Dave Osbourne ( 688888 ) on Monday December 11, 2006 @04:44PM (#17199388)
      Used to run an archiving business of sorts (trade stuff in exchange for space) on many towers of CDs. I burned in the mid to late 90s many CDs and have them all archived still. Went back and uploaded them to a terabyte raid I built and without one failure of the CDRs that I archived, not one degraded to not mount and copy. I had a few that had scratches, but that is a different story and not related. Bottomline, buy what works, cheap and don't move them once archived, keep in cool dark place, and you are good to go. Oxidation is a CD-ophile's issue, not much in the reality zone. Heat is an issue, and if you store them on your dashboard, you deserve what results.

    • Re: (Score:3, Funny)

      by Rob T Firefly ( 844560 )
      "(please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media)." And NEVER ever feed them after midnight.
      Do not taunt Happy Fun CD.

      • Re: (Score:3, Funny)

        by Kenshin ( 43036 )
        Do not taunt Happy Fun CD.

        Wanring: Happy Fun CD may install a rootkit on your system if it feels threatened.

    • Re: (Score:2)

      by r3m0t ( 626466 )
      Maybe you should download a program which checks the error correction codes on the CDs. You might find that some of them are almost unreadable but the error correction means that they work as normal.

      Your CDs are likely to fail all at (almost) the same time.

    • Re: (Score:3, Informative)

      by greg1104 ( 461138 )
      I got my first burner in mid-1996, so my early discs are over a decade old. I've seen a small but non-zero number of failures among the CD-R burns over time, maybe 10 discs out of over a thousand discs. Haven't seen any from the better quality gold media (Mitsui, Kodak), but a few from CD-R and DVD-R discs made with other formulations. The failures I remember the details of were from Sony (x2, but I used a lot more of these than the others here), 3M, Memorex, and Mitsui Silver (x3). At any time I normal

    • Risk (Score:2)

      by fm6 ( 162816 )

      I have yet to run across a burned CD I cannot read due to this sort of degradation. Maybe at the decade mark, some of my discs will fail me and I'll change my mind but right now I'm not too concerned.

      When a product has an expiration date, that's just a promise that it probably won't fail before then, not a guarantee that will fail. If your carton of milk expires on Thursday, it won't necessarily be sour on Friday. By the same token, your archive disks are probably OK well past the 10 year mark, but you hav

  • Bummer (Score:4, Interesting)

    by Deagol ( 323173 ) on Monday December 11, 2006 @04:42PM (#17199354) Homepage
    I always thought Matsui "Gold" and "Silver" were the top-rated media. At least for CD-Rs (though I thought they were held in high regard for DVD blank media, too). I used to mail-order un-branded blanks them by the spool.

    • Re:Bummer (Score:4, Interesting)

      by greg1104 ( 461138 ) <gsmith@gregsmith.com> on Monday December 11, 2006 @06:02PM (#17200456) Homepage
      Mitsui's gold media has generally been considered the best available for CD-R work, particularly from an archival perspective. The company has reorganized and now goes by the name MAM. If you look through the comments after the article, the author suggests that the currently available MAM media isn't as high of a quality as the older Mitsui discs. I would like to see some citation for that fact, as I wasn't aware the formulation was changed at all from that reorg, but I haven't researched this subject recently enough to be able to dismiss his suggestion outright.

    • Re: (Score:3, Interesting)

      by Firehed ( 942385 )
      Modded funny? I know that the moderation system on Slashdot is totally out of whack, but I fail to see any possible opportunity for humor in this post. Any of the In_ mods, certainly, but funny?

      Of course, I expect the requisite *woosh* response to my own post, but at least be kind and explain what I've missed when you do.

  • Safety in Numbers (Score:4, Interesting)

    by Doc Ruby ( 173196 ) on Monday December 11, 2006 @04:42PM (#17199356) Homepage Journal
    Cheap but adequate DVD-R media costs $200 for 1000 discs, about 4TB capacity. And a cheap DVD-R changer jukebox costs under $500, about 800GB per load.

    Why not just burn a few copies of the archive to a bunch of DVD sets? The DVDs will get defects, but shuffling the chunks across the discs just a little will probably ensure that the random distribution of specific defects will not hit every copy of a given bit, against the odds a low defect rate will produce.

    How about a pair of those archivers, which fire up every few years just to transfer the aging DVDs to fresh new ones? For another $1000, that's another 5 cycles of DVDs, 800GB per cycle. Another $1000 gets a pair of backup jukeboxes.

    For higher capacities than 800GB, there are pricier pro jukeboxes, but with dual drives for the retranscription cycle (and faster restores). But the architecture is the same. Why try to make the media more reliable, when there's cheaper/easier solutions that just accept unreliable media, and move on?

    • Re:Safety in Numbers (Score:5, Insightful)

      by ericdano ( 113424 ) on Monday December 11, 2006 @04:54PM (#17199538) Homepage
      Why not just get a NAS that has RAID? That would make more sense. When a disc dies, you can replace it, rebuild your array, and everything is fine. PLUS, you could expand your archive over time.

      I think it's absolutely stupid to use a DVD jukebox. Really. Look into a NAS box with RAID.
      • I think it's absolutely stupid to use a DVD jukebox.
        Judged by convenience/ease/performance, I agree. But no level of RAID tiering is going to help you with the one thing off-line (tape/removable disk) solves quite nicely: that is to say, our good friend, more-than-a-surge-protector-can-stop, lightning.
        • How often does that really happen? Really? Got Stats for it? Are DVD's capable of surviving a bolt of lightning? I think Fire would be more probable. Or Flood. But if that was happening, it would be rather easy to disconnect my ReadyNAS NV and take it with me in the car than a huge jukebox DVD thing.

          If you really want to be safe, have two NAS devices. One as your main one, for putting stuff on, and the other to make a backup of the NAS device. Or have the NAS backup itself to another drive. There are a numb

          • Are DVD's capable of surviving a bolt of lightning?.
            Yes -- They don't get hit, whereas all of the NAS products I'm aware of need power, and as a result are wired.

            With DVDs, you can have an off-line copy, or even store copies at alternate physical locations.
        • And neither will help with fire, unless you ship your offline stuff offsite.

          I use a RAID both at home and at my studio. At the studio, mostly empty warehouse but good fire supression, I also back up to tape. At home I have a wireless NAS inside a safe, but your comment just made me realize that lightining could actually set a fire inside the safe. Unlikely but possible I guess.
        • Tape systems are quite expensive. Even more expensive [zdnet.com] than HD solutions. I didn't think that was possible.

          • Re: (Score:2, Informative)

            by profplump ( 309017 )
            Only until you start making archives. Tape media is easily 50% cheaper on a per-GB basis once you get past the hardware purchase. With hard drives you never get past the hardware purchase.

            If all you want it a copy of the current (or the last few) day's disk state, then another disk makes good sense. If you want to be able to restore last December's tape because someone trashed your 1099-processing software in January and no one noticed until today, tapes are definately cheaper.

      • Re:Safety in Numbers (Score:4, Interesting)

        by Doc Ruby ( 173196 ) on Monday December 11, 2006 @05:41PM (#17200188) Homepage Journal
        With the single DVD jukebox, the first 800GB is online at one time, for $450. A 750GB HD costs $350. But the next 800GB in DVD costs only $40 - each 4TB costs $200. And there's no limit to how many $50 TBs you can archive, with a sizeable enough closet. The downside is un/loading the jukebox, 200 at a time. But that's archive, "nearline" storage.

        Plus, you get a DVD reader and writer. For dealing with the DVDs (and CDs) that still distribute lots of content as a transfer medium. And for those without distributed endpoints to where they can archive data, or insufficient network bandwidth to archive all their data across the WAN frequently enough, DVDs are good and cheap offsite archive repositories. Plus you can burn DVDs that will play in every consumer player, which can connect your data to lots of people without data processing HW. HDs are a cul de sac for data, trapped within the infosystem.

        DVD archiving isn't really competition to online HD storage. It's complementary, in different use cases, different user environments. There's considerable overlap in their related extremes, but there's a lot of difference that makes leaves the DVD solution worthwhile for many scenarios.

        BTW, while I'm offering detailed factual analysis of HD vs DVD mass storage, don't throw in your "opinion" that "it's absolutely stupid...". Especially if you're going to offer a disagreement worth considering. Do you want to work together to figure out the real merits in a debate, or do you want to get into an obnoxious pissing contest that few other people will want to wade through? Few people worth teaching will learn anything from such unnecessary conflict. Including ourselves.

        • Re: (Score:3, Interesting)

          by ericdano ( 113424 )
          "With the single DVD jukebox, the first 800GB is online at one time, for $450. A 750GB HD costs $350. But the next 800GB in DVD costs only $40 - each 4TB costs $200. And there's no limit to how many $50 TBs you can archive, with a sizeable enough closet. The downside is un/loading the jukebox, 200 at a time. But that's archive, "nearline" storage."

          But what happens if a DVD gets corrupt? Or scratched? Or, lost?

          "Plus, you get a DVD reader and writer. For dealing with the DVDs (and CDs) that still distribute l

          • Re: (Score:3, Informative)

            by Doc Ruby ( 173196 )
            In the original grandparent post to which you replied, I started out by saying that the point of the DVD changer is to make several copies of the same data, on different DVD sets. So if a DVD gets scratched, or otherwise ages (as detailed in the story which we're tangentially discussing), there's another copy. More expendable DVDs, instead of tougher ones.

            I'd say that the 4.7TB that $1K will buy, along with the DVD-R burner jukebox, is more than "little bits of data". I already pointed out how to deal with
        • Are there consumer systems for doing this, and are they reliable? Are the DVDs easily recyclable? I'd hate to be buying more and more stacks of plastic laminated metal that can't be recycled when they are no longer needed.

          I certainly don't want to be dealing with jukeboxes that fail. I knew some people that dealt with a commercial grade jukebox that was simply unusable, it would routinely drop media and otherwise misbehave.

          I'm also not interested in manually changing out discs.

          For me, it's all adding up
          • The $400 I cited is for consumer models like the Sony Vaio version for their home theater PC systems. I don't know how reliable, but I expect they probably are, and under warranty. But I still mentioned buying extras for redundancy.

            I don't know whether DVDs are easily recyclable, but I believe that they are more recyclable than are hard drives. Maybe not.

            Everything fails. HDs have MTBF, as do jukeboxes, though I don't know whether the consumer ones are either really tested and that spec published, or how hi

        • With the single DVD jukebox, the first 800GB is online at one time, for $450. A 750GB HD costs $350. But the next 800GB in DVD costs only $40 - each 4TB costs $200. And there's no limit to how many $50 TBs you can archive, with a sizeable enough closet. The downside is un/loading the jukebox, 200 at a time. But that's archive, "nearline" storage.

          Hmm, where can I buy that $400 jukebox that will also write my DVDs?
          Because with a single writer (or even a bunch of them) writing 200 discs is quite a painful pr

      • Re: (Score:2)

        by caseih ( 160668 )
        Don't mistake NAS for backup. We plan to implement a NAS and a DVD archive. Here's how it works. Every night the main array is snapshotted. We figure we'll easily have enough storage to maintain about 6 snapshots, given that we change an average of 6 GB of data a day. We'll copy the full snapshot off to backup disk (IE removable disks), about 2 TB worth of data. Then we'll take the snapshot and make ISO images of just the changed data which we'll write to a dvd. If we plan on keeping a year's worth of
      • NAS is a nice solution, but that doesn't solve the problem of off-site storage.

        I use NAS for my home business but still archive my work to DVD and send it to a relative to store. If my house burns to the ground or if someone breaks in and steals my equipment, I can still restore. If I had everything on NAS, it would be gone.

  • I agree... But where can I find some? (Score:3, Informative)

    by madhatter256 ( 443326 ) on Monday December 11, 2006 @04:43PM (#17199366)
    Taiyo Yuden All the way. They are great for copying PSX/PS2 games (seriously) where media quality makes a difference between burning out a laser or playing your back-up game, as well as DVD Movies.

    The only drawback is that you can only order them from the Internet. I do not know of any retail store who actually sells the brand outright nor do I know of any brand (like Sony, Memorex, Fujifilm) who sells rebranded Taiyo Yuden discs.

    Also, the Taiyo brand is more expensive than any other brand.

    • Re: (Score:2)

      by Tiro ( 19535 )
      Sony sells them, I think you just have to look for the ones that say "Made in Japan" I saw them in Circuit City, but the floor staff pushed me to buy the product with the big rebate instead.
    • The only drawback is that you can only order them from the Internet. I do not know of any retail store who actually sells the brand outright nor do I know of any brand (like Sony, Memorex, Fujifilm) who sells rebranded Taiyo Yuden discs.

      I'm told the Fuji's that are "Made in Japan" are usually Taiyo Yudens. I've gotten a pack of them at Best Buy (the country of origin isn't always the same) and they've worked well. I haven't gone the additional step of running a disc ID program on them.

      Usually I just order
      • Side comment....

        What's a good inkjet printer for printing on printable CD/DVD media?
        • What's a good inkjet printer for printing on printable CD/DVD media?

          Epson R200/220/300/340 series. I have the R300 [epson.com], and can't say anything but good about it. Prints look like it came from the factory.
          Epson has a refurb R340 at their outlet center for $70.
        • What's a good inkjet printer for printing on printable CD/DVD media?

          I'm using an Epson Stylus Photo R220. $89 or so and very good quality.

          If you're using a mac, e-mail me for an explanation of the right steps to open the printer doors in so the print driver doesn't drive you up a wall.

        • Re: (Score:2)

          by sane? ( 179855 )

          Canon ip3000

          At least if you are outside the US, the Canon's are probably the best at printing on CD/DVDs. Not sure what the current models are, but I've been using mine for ages, no hassles. The major advantage of the Canon models was always that you could use refills, no hassle. My cartridges cost ~£1 a shot.

          Unfortunately in the US, they blocked off the feed slot for the CD/DVD tray, because they didn't want to pay someone a fee.

      • Yes. There is a program out there that identifies a disc's manufacturer, and all the Japanese Fuji's I've bought have been Taiyo Yudens. Consequently, they're all I buy. I've never had one fail yet (and have had lots of other brands fail. (Such as, oh, about every other disc made by CMC Magnetics. Horrid.)

        I've also had good luck with the Verbatum "VideoGard" line. (DVD Identifier says the batch here on my desk is made by Mitsubishi Chemical.) Their particular gimmick is a hard, scratch-resistant coating wh

    • Re:I agree... But where can I find some? (Score:5, Informative)

      by mobby_6kl ( 668092 ) on Monday December 11, 2006 @05:05PM (#17199700)
      Some Verbatim DVD+Rs are manufactured by Taiyo Yuden. Strangely, the ones I used were the cheap-looking colored ones, but I've used several batches of those with excellent results. Speaking of Verbatim, some of their other discs are made by Mitsubishi, and those also very good, although I'm not sure how they'd work for PS2 piracy ;)

    • The secret to spotting Taiyo Yudens (Score:5, Informative)

      by traindirector ( 1001483 ) * on Monday December 11, 2006 @05:39PM (#17200162)

      I've seen Taiyo Yuden CD-Rs and DVD+/-Rs in a number of retail stores under various brand names. I'm hesitant to publicize my trick, but I suppose the Slashdot community should know. Here's how to spot Taiyo Yudens quickly in the store, without checking each label for "Made in Japan":

      The spindles all have a unique bottom lip. Whereas most plastic spindle coverings are the same diameter from the top of the spindle to the bottom, Taiyo Yuden cases have a "lip" on the bottom of the plastic covering that starts about an inch from the bottom. The bottom of the clear plastic covering sticks out just a bit and then recesses to the diameter of the rest of the spindle. Taiyo Yudens comes in these cases no matter how they are branded, and I have never seen a spindle of discs with this bottom lip that are not Taiyo Yuden. I guess Taiyo Yuden supplies the plastic spindles as well as the branding on top of the disc.

      In any case, I have had better luck with the consistency of Taiyo Yudens than any other brand of DVD+R. I'm not sure what the case is now, since I've only been using Taiyo Yudens for the past few years, but when DVD recording was first becoming affordable, the compatibility of much DVD media with various recorders was so terrible as to be useless (and endlessly frustrating). Taiyo Yuden makes quality discs, and it's always nice to spot them in the store when there's a deal going on.

      • Re: (Score:3, Informative)

        by drwtsn32 ( 674346 )
        Not sure your method is completely accurate. I have a spindle of DVD+R media from TDK with the lip you describe. The media is indeed Taiyo Yuden. I then checked a spindle of CD-R media without the lip. Nope, not Taiyo Yuden. So far your method looks good! But I have another spindle of CD-R media (Maxell) with the same lip as the DVD+R TDK media and Nero shows the disk as being made by Ritek. Damn!

  • Not a concern with MY optical media (Score:3, Interesting)

    by loimprevisto ( 910035 ) on Monday December 11, 2006 @04:43PM (#17199378)
    I have some movies on laserdisc that're pushing 20 years, and I haven't had a problem with them yet!
    • Yeah. Me too! Though a couple have laser rot on them. :-(

      But, I really wish I still had the double sided player. It died. I still have a single one though.....

      I have some disc in my studio, on the wall, and people always ask about them......

    • Yeah, but they're analog. When they do have a problem, how will you know? It'll just look like a slightly degraded picture or sound, which you might either not notice or might attribute to the player.

  • You don't get (Score:5, Funny)

    by sa1lnr ( 669048 ) on Monday December 11, 2006 @04:48PM (#17199448)
    direct sunlight in your parents basement. ;)

  • This bears repeating (Score:5, Insightful)

    by Daishiman ( 698845 ) on Monday December 11, 2006 @04:50PM (#17199470)

    Repeating again and again and again:

    For backups and archival you need tape backups, stored offsite. If you want something with more capacity and faster recovery, a backup server with rsync and beefy hard drives. Nothing else will do. With the time and effort you'll spend searching and writing DVD media you could have already bought and set up a file server or bought that tape drive.

    Unless you're going to be taking those backups with you and using them in high volume, backing up to DVDs is simply a waste of time and space, and when you get some dreaded CRC errors you'll be crying for not having done otherwise.

    sig: Cosas varias de un sysadmin argentino: http://aosinski.phpnet.us/ [phpnet.us]

    • What you're saying is probably true enough if you're in a business, in a position to have a file server and tape drive. But now let's imagine you're a home user with a laptop. You already have a DVD+-RW drive built in to your laptop and a 2 GB of personal data you want to archive. What are you going to do then?
    • While I appreciate the sentiment, there are still lots of valid reasons for wanting off-line storage in the form of DVDs.

      Consider the cost. Hard drive space is, at best, around $0.25 per GB? Ignoring the cost of the infrastructure you'd need (servers, RAID cards, etc.) to keep them running, that's still about 4x the cost of decent DVD media. (If you follow TFA's recommendations and go with DVD+R, about 2x.)

      I've been doing a lot of slide scanning recently, basically producing 3200 dpi x 64 bpp (64 because it

    • If you want something with more capacity and faster recovery, a backup server with rsync and beefy hard drives.

      Correct me if I'm wrong, but doesn't rsync pretty much fail for binary transfers? I was under the impression that rsync is really only useful when you have version X of something on your offsite server, and want to update it to version Y. Thus, rsync is great for logs, source code, or other text files, but is not really any more useful than

      if FILE not in OFFSITE_DIR:
      cp FILE OF

      • Sorry, I meant to finish that last sentence with:
        "...for binary files."

    • What are your thoughts on removable hard drives? Some of us [home users] don't want to spend the $2000 entry fee to get into tapes...

    • Re: (Score:3, Interesting)

      by Ucklak ( 755284 )
      That realy depends today.

      If you have a large organization and you're backing up terabytes+ daily, then yes with incremental. You can probably afford the $37,000+ for a TB storage solution.
      A good bit of small businesses really don't have more than a couple hundred gigs that need to be backed up and the nightly stuff is probably under a gig unless you're in the media business.

      Tape backup for archival is a horrible solution. You're dependant upon the media and the media player and in the case of Microsoft, the

    • Re: (Score:3, Insightful)

      by XSforMe ( 446716 )
      "For backups and archival you need tape backups,"

      I agree when it comes to backing up, but not necessarily on the archival issue. Whenever you are planning long term archival, your best shot is a nice laser print out on acid free paper. If this is simply not possible then your second best choice will be a media which you suspect you will be able to read in the next 25 years, and in this case my money is on CD/DVD rather than on a particular type of tape.

      Try getting now a days a QIC tape drive which will read

  • I have CDs good since 1998 (Score:5, Interesting)

    by scottsk ( 781208 ) on Monday December 11, 2006 @04:50PM (#17199486) Homepage
    I now have some no-name-brand CDs burned in 1998 that are still good. I have never had a good, name-brand CD fail for any reason. The only failure I have ever had was the top layer peeling off some el-cheapo CDs which were stored in plastic sleeves, not jewel cases. One BIG key the article does not mention is to store the disc where the burned surface is not touching anything, such as in a jewel case -- the article should have mentioned that. Do not put in plastic sleeves or cases with slide-in sleeves. Odd that the article is a sales pitch for that T-Y brand -- what about RiData? That's what I use for DVD archival storage. I haven't been using DVD-R long enough to comment on how long they'll last. I have always found the alarmist idea that CDs will spontaneously self-destruct to be sort of over-the-top. CDs seem much more reliable for archiving than any other medium like diskette, hard disk, USB flash, or tape. Flash is more reliable, but has to be refreshed or it will disappear.

    • Re:I have CDs good since 1998 (Score:5, Insightful)

      by slamb ( 119285 ) * on Monday December 11, 2006 @05:17PM (#17199860) Homepage
      I now have some no-name-brand CDs burned in 1998 that are still good.

      Probably using the original dyes, then? According to the article, they are most likely to fail in 2008:

      The first organic dyes, designed by Taiyo Yuden, were Cyanine-based and, under normal conditions, had a shelf life of around ten years; simply, that was simply unacceptable for archive discs.

      These people are talking about serious long-term archiving, not "it worked for this one guy for eight years".

      I haven't been using DVD-R long enough to comment on how long they'll last.

      No one has successfully used them as long as these people are talking about; they haven't existed that long. The lifespan claims are made from an understanding of chemistry (theory) and accelerated aging techniques (experiment).

    • RiData sucks. Seriously, I'm not trolling, I've been backed up on this [digitalfaq.com]. Not to mention I've personaly had RiData discs fail on me within a month of burning, their double layer DVDs are good for nothing but coasters, and I have an entire spindle of RiData CDs with visible defects on them. How the hell did that get past quality control?

      For me, it's Verbatim all the way.

    • ...when the label peels off. I don't know who the OEM was. I usually buy Sony CD-Rs now (and avoid Imation).

      I have also previously read that DVD-R was slightly more compatible with most readers, but the error correction discussion below makes me want to switch.

      The DVD-R specification states that for every 192 bits, 48 of them are not protected under any scheme, 24 of them are protected by 24 bits of parity, and the last 56 bits are protected by another 24 bits of parity. This weird (to put it mildly) s

  • my experience: some DVD media dies with no reason (Score:3, Interesting)

    by Anonymous Coward on Monday December 11, 2006 @04:57PM (#17199580)
    One Maxell DVD-R I burned in Sept. 2003 went bad within 3 years, despite every detail of the burning, readback, handling, and storage being in accord with the advice I've seen posted. An email to Maxell support on this issue had the reply: "The media if stored properly will have a life of at least 50 years."

    Possibly relevant, I noticed an internal pattern of small spots visible with a loupe or macro lens (on order of 10 microns in size; much larger than the data pits). You can read more about it here: http://www.bealecorner.com/trv900/DVD/Maxell-DVDR- spots.html [bealecorner.com]

    Maxell America agreed to take back this DVD for analysis. As instructed I sent it to their Fair Lawn, NJ site. It was received Oct. 5 2006 and Maxell acknowledged receipt. They have apparently done nothing with it since, despite several emails to them in the ensuing two months.
    • Maxell is the only brand of CD-RW that I ever had problems with. I had 3 from a pack of 5 die after the 1st erase, And a Dual Layer DVD-R produce a pretty expensive coster. The only other brand to always mess up was some no-name junk that an old employer had sitting around for free, can't remember the name of it but had a ugly white and tan label, I think it was Computer Peripherals.

      The only other CD I know that is not working is a TY disc, ink printable white label burned about 1 year ago. No scratches at
  • The only way to get your stuff to last more than a generation is to chisel out yer 0's and 1's on clay tablets...

  • I use DVD+/-R over CD-R for archiving. (Score:3, Interesting)

    by Vellmont ( 569020 ) on Monday December 11, 2006 @05:04PM (#17199670) Homepage
    The reason being that DVD+/-R has the recording surface sandwiched between the two layers of plastic. CD-Rs have the recording surface on top, which can flake off unless you handle it very carefully.

    Sure, you can handle the CD-Rs carefully and avoid this problem. But wouldn't you rather use a more reliable medium in the first place?
  • Here's my two cents:

    Stay away from Taiyo Yuden 16x media. I'm using a BenQ 1620 for all my DVD burning needs, and the PI/PO tests done on T-Y 16x media using DVDInfo Pro [dvdinfopro.com] have always resulted in low quality burns. I am currently using 8x Verbatim DatalifePlus DVD+R media, and burning them at 4x. The results are truly unbelievable. The media code on the 8x Verbatims is MCC 003. I've heard through the grapevine that T-Y changed their media somehow from their 8x sets to their 16x sets, which has resulted i

  • DVD media quality guide (Score:2, Interesting)

    by noky ( 631168 )
    I have found this dvd media quality guide [digitalfaq.com] to be extremely informative. Yes, Taiyo Yuden is always ranked at the top (and is what I use), but they are not readily available at local retailers. It really helps to have a detailed comparison of various media instead of just saying "brand X is best".

  • Out of direct sunlight, cool dark place (Score:3, Funny)

    by blantonl ( 784786 ) on Monday December 11, 2006 @05:44PM (#17200230) Homepage
    please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media

    Well, it's good to know that 95% of slashdotters are already following this practice by inherently storing their media close to themselves, next to their computers.
  • There's no dye fade with RW formats. He didn't even bother to touch on rewritable media. I imagine they'd be much more resistant.

    • He didn't even bother to touch on rewritable media. I imagine they'd be much more resistant.

      He did mention briefly that RW media are out of the question for archival purposes.

      To make a completely unscientific point, I'd imagine there's a reason for having different technologies for R and RW. If RW media outlasted R, why would there be R media at all? For example, many audio CD players don't play CD-RW, but they play CD-R perfectly. This should tell something about the relative merits of the media.

  • No mention of these [dansdata.com] yet, so thought I'd let everyone know. The DiscSavers cases are great for fragile DVDs. It keeps them safe, and gives you easy access to them. Try dropping one of those on the ground and you'll see it doesn't result in scratches and broken cases. Highly suggested for anyone planning on storing any burned DVDs for any length of time.
  • Is it just me or does this subject come up once a month or so?
  • I create par2 files of all the videos and other large files I burn to DVD. It takes a while, but I know that I can have a 30% failure rate and still generate all my data.

    Maybe someone could create special hardware to make par2 take a reasonable amount of time?
    • dvdisaster [sourceforge.net] does the same thing basically but is easier if you intend on making error correction codes for entire discs.
  • There was a time, years ago, when CD/DVD archival made sense. These days when the HD prices are so low, I just don't see the benefits.

    I have a box sitting in my friend's "office" in a different country - could just as easily be in a friend's house in a different town ...as long as it's not in an area that is likely to be hit by the same disaster as your home.
    Currently, in addition to the drive the OS is on, it has a mirrored pair of 700 GB drives - this is enough for _MY_ current needs. It holds compressed

  • The usual vague personal testimony... (Score:5, Interesting)

    by dpbsmith ( 263124 ) on Monday December 11, 2006 @06:31PM (#17200848) Homepage
    Oh, I'm so tired of these articles. Everyone concentrates on dye fading, because I guess it's easy to measure and quantify. If dye fading were the failure mechanism for these disks, they'd last twenty to two hundred years... according to vendors and researchers.

    Everyone says "I've never had any trouble with brand ABC," but the thing is, ABC varies depending on what you read or who you talk to. Some people insist they've never had any trouble with the cheapest generic products they buy at Staples. Some say any name brand is OK. Some say Verbatim is good. Some say to stay away from Verbatim. The more sophisticated will tell you not to use anything but phtalocy- pthalocy- pffthal- the Mitsui stuff. Others (like this guy) are partial to other dyes. Some say you're a fool to use anything but Mitsui Gold... some say they're an overpriced waste of money.

    It's all authoritative sounding talk, talk, talk and no two experts say the same thing.

    In reality, I don't think anyone understands very well what actually causes these disks to fail in the real world. I've had disks fail in less than two years--maybe only a couple-three in many hundreds, but certainly not zero--and I've never seen any obvious pattern as to which of them fail.

    The thing that really bothers me is that drives and/or their accompanying software drivers never give you any indication of what the signal quality of a particular disk is. If they did, you could detect that a disk was deteriorating before it failed, and make a copy. As it is, they just keep silently keep correcting errors behind your back and you have no warning until there is utter, catastrophic failure.

    • Re: (Score:3, Insightful)

      by epine ( 68316 )

      Have you ever heard of bait and switch? It's a deeply engrained trait in the human species. Under one set of conditions, such as not having much credibility to begin with, an organization will work very hard to establish the reputation of a product line. Then under another set of conditions--major stakeholders change chairs, new management team recruited, under a short-term cash-out-now incentive structure--all the expensive magic that made the original product good is discarded, and the newly watered do
  • I highly recommend doing your archiving on the cheapest, poorest quality DVD-R discs you can find. The reason is simple: thinking you have high-quality media makes you complacent about testing and migrating archived data

  • The author makes a statement in his article that gold layer DVD's are not feasible. In actuality they are offered by Misui / MAM-A in a couple of different grades. I'd much rather use them than Taiyo Yuden for important data.

  • Never, ever use printable media for backups. It always lets you down. Nuff said.
  • In Canada you can get Taiyo Yuden from www.blankmedia.ca

  • Taiyo Yuden FAQ (Score:3, Informative)

    by Foresto ( 127767 ) on Tuesday December 12, 2006 @02:32AM (#17204648) Homepage
    Taiyo Yuden FAQ [cdfreaks.com], for those who want guidance in finding these discs.

  • independence (Score:3, Interesting)

    by chucken ( 750893 ) on Tuesday December 12, 2006 @09:00AM (#17206480)
    Am I the only one to be suspicious about the impartiality of this article? Check out the links. Quite a lot go through the weird ass domain name JDOQOCY.COM. Do a whois on this domain and you'll find the registrant is "Commission Junction". Hmm, impartial, NOT.

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