How to archive on disk drives

How to archive on disk drives

Summary: Archiving on hard drives?Now that disk drives are cheaper per gigabyte than tape cartridges, you might be tempted to archive data on disk drives and stick them on a shelf.

TOPICS: Storage, Hardware

Archiving on hard drives?

Now that disk drives are cheaper per gigabyte than tape cartridges, you might be tempted to archive data on disk drives and stick them on a shelf. Don't do it! Your data won't last.

The reason: the bits on the hard drive will gradually lose their magnetism, sometimes in as little as 12 months. Disks automatically rewrite marginal data blocks on the fly.

That doesn't happen when the disk is powered off.

The big guys do it Enterprise storage arrays do disk grooming in the background. They also look for bad blocks and other problems that are less painful to fix when the system is running normally.

Some arrays spin down or even power off disks to save power and cooling while extending drive life. These systems include logic to power up drives and check the data on a regular basis.

So leave that drive plugged in! If you want a couple of extra drives for archiving just buy some USB drives. They are cheap and work with any system. At idle they use about the same power as a nightlight.

The Storage Bits take Disk drives are used for archiving all the time. But they aren't just powered off and put on a shelf.

If you need that, buy a tape drive. Properly stored tapes will last for decades.

Comments welcome, of course.

Topics: Storage, Hardware

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  • Do you have some references to backup your claim?

    I am curious, do you have any references to backup your claims? 12 months?

    I have never heard of this before and interested to see the research.
    • Disks aren't stable. Tape is, it has a high bias.
  • RE: How to archive on disk drives

    well it is known that magnetism loses its polarity after a given time, which is why when i have data i want to keep around i just copy from one drive to another. afterall it has to read the data and write it back. I probably due this every 6 months or. Doesnt mean that the data loss will happen at that point , it is just when i happen to do

    what is the flux rating, in oersteds, between tape and hard drive? is this why data can last for decardes as opposed to months on a hard drive? which implies, if i recall correctly, that the field of magnetism has to be larger on a tape?

    no time for fact checking. you wrote the article, go back it pun intended
  • RE: How to archive on disk drives

    How about External Harddrives like Seagate's Free
    Agents etc? Cant I use them for backups? Thanks.
    Mahmood A
  • RE: How to archive on disk drives

    Your premise is flawed. How do you think data is stored on tape? MAGNETISM.
    Data stored on tape does not last decades, even when stored under perfect conditions of humidity and temperature (and I seriously doubt any home users control humidity to the degree noted in the fine print on tapes).
    Industry tests (not spec sheets but actual tests) recommend storing no more than 4 years. I actually tested the retrieval of data off of 40 tapes all 4 years in storage. I was only able to get intact data off of half of them.
    Though my actual results were worse than normal - what good is it if even ONE tape is unreadable?
  • I fired off an old Win98...

    machine I haven't had on in 5 years. Bit sitting in the garage. No lost data here. Must be a miracle machine.
  • Twelve-Year-Old Quantum Still Perfect

    I think that maybe someone is overestimating the rate of data loss/corruption. Earlier this summer I was sorting my "museum of computer memorabilia" A.K.A. "junk closet" and connected up some drives that had been sitting for up to twelve years. I had no problem reading twelve-year-old data from a Quantum 4.7gB SCSI drive beyond finding a controller that would fit into any of my current machines. Only one drive from the box full had problems that sent in on a dumpster dive.

    As an aside, there were two DAT drives in the closet too. Only one of them would work at all and none of the tapes from storage were readable without errors.
  • I call BS!

    I call BS, unless its something new built into the 500-1TB+ drives.

    I've plenty of digital video files on drives that are well over 12 months on the shelf unused. In fact just last week I was looking at some of the oldest to transfer from 60GB drives to larger drives to make more efficient use of the carriers and recycle the 60GB drives to some old lab systems that don't support bigger than 64GB drives.

    As long as we're making unsubstantiated claims, sometime around when USB2 came out MS seems to have "updated" firewire drivers so that large (13GB+) file transfers fail. I can put the same drive into a Firewire/USB2 enclosure and the file transfers without errors over USB but not 1394. I'm seeing this with TI and Via firewire chips.
    • Don't blame this on Microsoft

      This is a problem with the TI and Via Firewire chips,
      NOT with Microsoft doing some 'nefarious actions' with
      your drives.
  • RE: How to archive on disk drives

    I suspect old drives work fine because the data is written much more broadly on the drive (magnetic domains are MUCH larger). New drives are MUCH more compact and prone to failure if just a few magnetic particles randomly flip orientation.
  • RE: How to archive on disk drives

    I think most of the posters here can say it hasn't happened to them but really would you want to risk it? If there is a chance of losing data would you really want to risk those archives. It's not back up data but archives. In some cases you might keep this stuff for a decade.

    I've popped an old harddrive in and looked some of my old data from time to time before formatting it for some other stupid use. Never had a problem but I wouldn't load a disk, stick in on shelf for 7 years then hope it's all there when I next plug it in.
  • The only ABSOLUTE way to preserve data ....

    is on archival grade, acid free, punch cards stored in an air conditioned, humidity controlled vault. Just check with the Smithsonian! (Another fact made up on the fly - thank you very much!)
    • Even then, it isn't absolute

      The fact is that most DVD discs will last, in normal
      household temperatures of 72-80 degrees, at least 20
      years. And that is DVD-R's. If they are original
      DVD's.... you are looking more at 100 years unless they
      get a scratch on them or something similar.
    • but what

      happens if the writing machine doesnt properly push the paper thru so you get a proper write and when you go back to read it the paper flips back shut?

      sounds like hangng chads then.....
  • Drives don't scare me as much as ....

    The only time I've "lost" data is when a hard drive fails totally (rare(, but I am having "mystery" data corruption on a weekly basis since getting my new Vista laptop. Funny how most of the posts on this issue go unanswered.
    • Here is an answer for you

      BS! There is no reason why you should be having
      mysterious data corruption, unless your drive is slowly

      Have you tried taking it out, getting a new drive,
      putting all the info on the new drive and seeing if you
      still get the corruption? Or, looking for new drivers
      for your devices?

      This is NOT a Vista problem, idiot. It's more a driver
      issue or a dying hard drive issue, and I fix computers
      for friends and relatives and are A+ certified, so I
      know what I am talking about.
      • what if

        the idiot in question actually did all that, verify drivers to be the newest, his hardware is all good

        you must have a horrible bedside manner as a tech dealing with the public by insulting them

        im a+ certified too and have never called anyone an idiot.

        try educating them so they understand what is going on with their systems

        tech since 83
  • RE: How to archive on disk drives

    Where can I get a tape to back up my 2 TB RAID disk set? Then in 20 yrs where can I get a tape drive to read it? BTW, if you say use my old machine, how will I transfer the data to another computer - I guess I'll need to copy it bit by bit by hand - the punch card option mentioned above is sounding pretty good right now.
    • A few facts about punch cards.

      I never had the dubious privilege of working with punch cards although I just missed that era by a few years. I tried to do a little research on punch cards and came up with the following:

      Price of a box of 2000 cards: was $35, more today.
      Weight of a card: 2.42 grams punched weight.

      cards per Gb = 1024^3 / 80 = 13,421,772
      tons per Gb = ( 13,421,772 * 2.42 ) / 453.59(grams/lbs) = 35.8 tons

      How are punched cards looking to you now? :)
      • One more important fact that I missed

        13,421 / 2000 = 6710.8
        6710.8 * $35.00 = $234,881