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Recent Sales Hint That Tape For Storage Is Far From Dead

Posted by timothy on from the didn't-you-know-that-tar-is-sticky? dept.

hightechchick writes "Staples' business-to-business sales of backup tape for storage are experiencing a bit of a revival. What's next, a return to dumb terminals and mainframes (a la cloud computing)?"

24 of 228 comments (clear)

  1. Not news. by SatanicPuppy · · Score: 4, Insightful

    What else is there? It's not like you can back up to a SAN, and then stick the SAN in a courier bag and send it to remote storage. Optical? Too small. The magical "cloud" doesn't stack up well for security compared to a physical safe. Flash is promising, but still not there in terms of reliablity.

    When they come up with a compact, reliable, portable storage medium I'll be the first one to toss tapes out the window. The idea of running backups to some credit-card sized SD cards is appealing.

    --
    ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
    1. Re:Not news. by h4rr4r · · Score: 4, Insightful

      You could not be more correct. It also needs to be as fast as LTO-5 or LTO-6 when that ships. That means 140MB/s or 270MB/s, and at least close to it for long periods of time. Those cheap SATA discs the kids keep suggesting don't come anywhere near that.

    2. Re:Not news. by X0563511 · · Score: 4, Insightful

      I (and many others) don't trust hard drives _at_all_ - let alone when you move them. This is learned behavior...

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    3. Re:Not news. by Pinky's+Brain · · Score: 3, Interesting

      Modern cheap SATA drives have average linear read and write speeds of around 120 MB/s.

    4. Re:Not news. by h4rr4r · · Score: 3, Interesting

      Please name a disk that can keep it up for the whole disk. This will be 1TB+ of random data written in 1 shot.

      I have not seen any yet, but would love to find one.

    5. Re:Not news. by SatanicPuppy · · Score: 4, Insightful

      Yep yep. Too many moving parts. You can drop a tape, and 999 times out of 1000 it'll be fine. Hard drives? Hell, it could die of vibration damage in transit!

      Tapes are small, disposable, cheap, reliable. Hard drives are maybe 2 of those.

      --
      ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
    6. Re:Not news. by afidel · · Score: 3, Interesting

      Dude, my biggest problem is keeping the damn LTO4 drives fed at MINIMUM write speeds for file server type small file workloads. 72x15k spindles isn't enough with only one volume being backed up, metadata retrieval makes it too slow, I need to have multiple volumes backing up simultaneously to keep the things from shoeshining.

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
    7. Re:Not news. by sexconker · · Score: 5, Insightful

      You're an idiot, Starscream.

      Tape is not legacy - it's the industry standard.
      Believe it or not, being old is not the same as being obsolete.
      In fact, in this industry, being old is a testament to how reliable something is.

      Compression? Deduplication? Seeding remote sites? What fantasy world do you live in?

      Tape is a storage medium.
      You can compress anything and store it on the tape.

      Deduplication is not a backup mechanism.

      Backups need to be made before going live and routinley afterward. Full backups.

      Tape is easy to restore from. You need full/incremental backups with tape exactly as you need them with a remote location. If it's attached to a machine it's a copy, NOT a backup. A backup must be remote, unpowered, and protected from Earth, Fire, Wind, Water, and Heart (thieves) etc.

      It's not difficult to know if data is safe. Just try to restore it. If you're not testing your restore process, you're an idiot, regardless of what method you're using. Tape is the most reliable storage format we have today.

      You can reuse tapes all the time. Such inefficiencies only matter if you're backing up data that's a fraction of a single tape. If this is the case, just buy more tapes. They're very cheap. If this is not the case, then you'll never run into the problem because each tape you write to will be part of a set of tapes corresponding to an individual backup job, and all but one of that set will be completely utilized.

      It's not a needless nightmare. It's a necessary nightmare. And it's not a nightmare. There's this thing called a label maker. Alternatively, labels and a Sharpie. Alternatively still, tape, paper, and a pen.

      No sir, it is you that deserves the beating.

    8. Re:Not news. by afidel · · Score: 3, Informative

      Yep, but that's what it takes to keep it running above minimum speed, writing a single large filesystem volume takes longer than writing 4 volumes almost as large because the drive shoeshines with a single job. Minimum rate for the drive is 40MB/s, the best I have done with tuning on a 72 drive vraid6 volume is 35MB/s and average is closer to 25MB/s sustained but 4 jobs from the same array on different volumes will give me 100-120MB/s. All volumes are spanned across all disks so it's not a matter of more spindles being available, it's the latency in all the metadata lookups.

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
    9. Re:Not news. by fuzzyfuzzyfungus · · Score: 3, Insightful

      I think you answered your own question there. Tapes are relatively cheap. Tape Drives are Not. Therefore, unless you are a large enough outfit to be amortizing the cost of the tape drive across a large number of tapes, tapes are effectively expensive. If you are, though, tapes are effectively cheap.

    10. Re:Not news. by KDR_11k · · Score: 5, Insightful

      Yeah but accessing your drive contents only through iTunes would be pretty clunky.

      --
      Justice is the sheep getting arrested while an impartial judge declares the vote void.
    11. Re:Not news. by totally+bogus+dude · · Score: 3, Insightful

      That's not much use if you want to be able to restore the individual files from the backup, which is nearly always desirable.

      Disaster-recovery-only backups are okay, but if you're spending the money to archive your data you normally want a bit more flexibility.

      Additionally there's the obvious problem of taking the server offline while you do the backup...

    12. Re:Not news. by totally+bogus+dude · · Score: 3, Informative

      Points in favour of tapes:

      - most backup software is designed to deal with tape libraries, not so much with shuffling B2D media around

      - most archive companies are built around storing tapes; though I suspect there are ones which could deal with hard disks in external caddies

      - tapes deal with stress from being transported continuously better than mechanical drives (also wear and tear of plugging and unplugging the interfaces all the time)

      - I think unused tapes age better than unused hard disks, but I've nothing to back that up

      Bandwidth to the tape drive itself rarely seems to be an issue for actual backups, since network and file I/O latency seem to be more significant issues. We never get anywhere near the maximum speed out of our LTO-4 drive, even when we're just duplicating data from the local array to the tape.

    13. Re:Not news. by jimicus · · Score: 3, Insightful

      I actually re-read this post several times because I wasn't too keen on the tone. I'm not having a go at you, but I was running the numbers myself on a spreadsheet only about a month ago and was expecting similar results to what you suggest.

      I was totally wrong. Right now, for any non-trivial quantity of data which is expanding at any non-trivial rate, LTO4 is the most cost-effective solution. (Actually, the most cost-effective solution is probably an LTO-5 drive but use LTO-4 tapes until the LTO-5 tapes come down a bit in price).

      100MB/s is plenty. Consider the cost of the whole deal: interface card, drive, cleaning tape, aggravation of having to switch tapes/run cleaning job, and so on. Three external USB 2.0 drives beat that speed, and cost a whopping $420 at Walmart, of all places.

      Please explain to me how you maintain 100MB/s write speed on a bus which can - on a good day - manage just under half of that. And usually manages more like about a third.

      Assumptions:
      - the tape has a lifetime of 300 passes, capacity of 1.5TB and $100 cost

      Or you could buy LTO4 tapes which will write just fine in an LTO5 drive and right now are quite a bit cheaper per gigabyte.

      - the drive lasts 3 years and costs $2000 (given my experience with LTO, that's optimistic)

      Are you not getting a 3 year warranty on your drive?

      Assuming that nothing gets any cheaper over time,

      Really? I'm buying LTO3 tapes for about a third what I was paying a couple of years ago.

      With my luck, half of the tapes had errors after one year, and that was on a lower density tape (VS160).

      Seriously, if half your tapes have errors after just one year, there is something seriously wrong. I don't know if it's power, environmental factors, cheap tapes or what but there is no way you should see a failure rate that high.

      For LTO, I'd think that you'd want the backup will be written, then verified, and then any data that had errors will be written again. So the number of passes available from the tape's life shrinks by half to 150.

      You are aware that the LTO specifications include automatic verification as part of the writing process? You generally can't turn this off.

      150 passes lets you use one tape to store and verify a total of 225 TB of data over its lifetime.

      Splitting hairs, but LTO writes a full tape in several passes. A tape will last several thousand passes, but probably only about ~150-200 complete fills.

      Pictures explain this far more clearly than text at http://www.lto.org/technology/primer2.html

      How does that stack up to the hard drive? A USB 2 hard drive will transfer 3.9 TB per day,

      Unless your users will put up with the performance hit that comes from taking backups during the working day, it doesn't really matter how much you can transfer per day. What matters is how much you can transfer during your backup window.

      Now knowing that tape prices don't really drop much with time,

      Which is wrong.

      With USB or eSata HDs, the interface costs are essentially nil, and most any current server comes with enough connectors to plug in several external drives at once, and the chipset is fast enough to keep them saturated if your source storage allows. You won't really be throwing multiple $2k tape drives at a bandwidth problem, but with USB or eSATA HD, the bandwidth comes essentially for free: as long as you have enough drives, each drive adds to the bandwidth.

      Not true, you'll be limited by the bus speed very quickly indeed. Just because your system has 8 USB ports does not mean you can expect to see 8x480Mbps when you've got 8 hard disks plugged in.

      With tapes,

  2. Offsite backups... by nweaver · · Score: 3, Insightful

    Although disk is compellingly cheap, if you want reliable, multiple, and offside-stored backups, tape really is the answer.

    --
    Test your net with Netalyzr
  3. What's Next? by Monkeedude1212 · · Score: 4, Funny

    I'll tell you whats next...

    A device that lets you type up a word document and it prints it out real time. Essentially it prints your keystrokes as soon as you press them. I also foresee it having an extremely long battery life.

  4. Mainframe and tape by tooyoung · · Score: 5, Insightful

    I'm guessing this story was posted by someone with absolutely no experience with enterprise-level businesses.

  5. Real link by phantomfive · · Score: 4, Insightful

    Here is the real link that is missing from the summary.

    I always wonder about tape backup.....it seems everyone I know who uses it has had it fail. Hard drives fail too, it's true, but the anecdotal evidence I have says if you are using tape backup, you better have multiple backups.

    --
    Qxe4
    1. Re:Real link by h4rr4r · · Score: 3, Insightful

      Live backups fail the minute you have a real big failure. Unless you have multiple sites and a huge pipe between them. Then you still should have tapes off site so one employee can't go destroying all your nice backups when he goes nuts.

    2. Re:Real link by h4rr4r · · Score: 4, Insightful

      You check the tape at the end of writing it. Everyone does this. You also test your backups, if you are not testing them you do not have backups.

    3. Re:Real link by TooMuchToDo · · Score: 3, Interesting
      More than 17,000, all stored in huge Storagetek libraries:

      http://upload.wikimedia.org/wikipedia/commons/e/eb/Storagetek-tape_drive_hg.jpg

      More info on CERN's infosystems for the collider, as they're the Tier-0 site (which means, in realtime, they take the raw detector data, strip it to the bare essentials, and than shove it out to Tier-1 sites at up to 40Gb/s (depending on the detector/experiment):

      http://news.cnet.com/8300-11386_3-76-2.html?keyword=CERN

  6. A revival? by Sycraft-fu · · Score: 4, Insightful

    Did it ever go away? As far as I knew it was always how you did long term backup. We just bought a new tape unit here since we needed more backup storage, and the development of new LTO formats continues apace. Disks are what you use for online storage, and for online backups, you have redundant disks. That is for sure our first line of defense. We have a RAID-6 system with hot spares. Ok, but what about if something bigger happens? I'm not just talking about facilities destruction, what happens if something goes apeshit in the storage system and screws up all the data (or maybe a malicious admin does)? If our backup is just a realtime hookup to another online system, we are screwed.

    Tapes though, the protect for a lot of things. We take regular backups, in rotation, so that even if the online system is messed up, there are backups to go to. Those backups can also easily be rotated to secure storage facilities. These are places that aren't easy to have an online system, even if you wanted. You are talking like a vault or something to keep it safe even in extreme situations.

    They are also great if we want to keep data for a long time. Tapes have good shelf life. Better than a HDD. This is largely because they are simpler. They are just, well, tapes. Retension them once a year, they can last decades.

    So I wasn't aware tapes had gone anywhere. We sure don't use them on individual machines, or use them as fast backups, but they are wonderful as an emergency backup. The protect against a number of issues that an online disk system can't. They can also easily give you the benefit of offsite backups for a much lesser cost. Costs a lot more to get a second high end storage system and house it in another building with fibre than to just walk some tapes over to a vault.

  7. Let's not forget Escrow by frooddude · · Score: 5, Informative

    The business I work for goes through tapes like they're used to make coffee. Primary use: legal escrow of source code.

  8. Paper or plastic? by quenda · · Score: 3, Funny

    For *real* archiving, you cannot beat paper tape. I don't trust it unless I can see the holes.