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How Often Do You Replace Your Hard Drives?

Posted by ryuzaki0 on from the mean-time-between-failure dept.

Telemachas asks: "I recently purchased a Dell P4 2.8 GHz swap meet computer with a 200 gig hard disk for a good price and all is working fine. It does not seem prudent, however, to trust my data on a swap meet item. For another @ $ 75.00 each I can purchase new 200 gig HDDs. I would also like to do my first RAID system. I am now wondering how often, if at all, do Slashdot readers replace their HDDs?"

12 of 254 comments (clear)

  1. Uhh... by Omeger · · Score: 5, Insightful

    When they break?

    1. Re:Uhh... by Anonymous Coward · · Score: 5, Insightful

      Of course. For HDDs the Time Between Failure distribution is just too broad.

      If you replace them on a schedule, you're still not guaranteed 100% reliability because a drive can fail way before MTBF, and you waste the drives that wouldn't fail if you had kept them. Seems like a lose-lose situation to me.

      So backup often, or use RAID. Replace the HDDs when they break.

    2. Re:Uhh... by gameforge · · Score: 4, Informative
      I entirely agree with everything you said, except this (minor nitpick, if nothing else):

      So backup often, or use RAID. Replace the HDDs when they break.

      There's really no replacement for backing up your files.

      RAID 5 (or mirrored RAID, if that's your favorite flavor) protects against a single hard drive dying. But if the RAID card dies, you lose everything, especially if it's a proprietary card that's hard to find (more likely on a personal server); I've tried interchanging 3ware controllers and Highpoint controllers, and they couldn't read each other. Additionally, if more than one drive dies, you lose everything. Or, if there's some other problem (you know, the one you didn't think about before you setup the RAID) and the array gets corrupted somehow... well, you lose everything.

      RAID can be a good supplement in addition to regular backups, but it's not a complete replacement.
    3. Re:Uhh... by Silver+Sloth · · Score: 4, Insightful
      Seriously. The older a drive is, in my experience the less likely it is to die. The first six months are the worst.
      This is known as the bathtub curve. If you plot failures against time then there is a high level at the beginning (the tap end) which decreases quickly as any weak or substandard components fail. Then there is a long flat bit as everything runs as normal with a (hopefully) low chance failure rate. Finally, as the components reach their end of life the failure rate begins to rise giving the shape (well, use your imagination) of a bathtub.

      With hard drives the far end of the bathtub tends to be obscured by obsolescence.

      --
      init 11 - for when you need that edge.
    4. Re:Uhh... by tibike77 · · Score: 4, Funny

      Why REPLACE a drive when you can ADD a drive ?
      Besides, whoever already said "the older a drive is, the least likely it is to get broken" got it pretty right.

      And, as for "permanent storage"... why would you EVER trust your HDD and your HDD only to "keep data safe" ?
      Everything that's critical (and not so secret) goes as soon as possible on a backup CD/DVD (the more the merrier), on other home/office computers, even on memory sticks or whatever other removable media you might have at hand... and if possible, also some remote (and remotely accessible) location.

      Or you could do it the "really tough guy way"... you know, the way of "I don't make backups, I put it online and let everybody else mirror it".

      --
      By reading this signature you agree to not disagree with the post you just read.
  2. Do Raid 1, replace when 1 goes down by Salvance · · Score: 4, Insightful

    For home, I never replace a drive unless one goes down. I just have one drive backup to the other (and vice versa) at night, then store my important files at work.

    At work, we have everything setup as Raid 1, and only replace drives when they go down, which is rarely. Not sure if this is the best approach, but considering we take offsite incremental backups every 15 minutes it's not really a catastrophic event even if both go down.

    --
    Crack - Free with every butt and set of boobs
  3. One day too late by Anonymous Coward · · Score: 5, Funny

    One day too late

  4. Good Luck w/ HDD's, Bad Luck w/ Power Supplies by gameforge · · Score: 4, Interesting

    I started building computers twelve years ago.

    The only drive I've had die before I retired it myself from sheer obsolescence was an IBM 20GB "DeskStar" model; this happened about five years ago, IIRC. The drive made noise and froze the system when I would read particular files; to my frustration, it occurred when I read some of the files that were important to me (documents, programming projects, one folder of MP3s, etc.)

    My solution was to put the drive in the freezer for a few hours; UNBELIEVABLY, it worked - I would have about ten minutes to copy as much as I could off the drive before it would start making noise again. I got most of what I needed off of it.

    Incidentally, IBM was very good about the whole thing; they sent me a new drive the day I called them. Too bad they sold their HD division to Hitachi...

    Anyway, I've had FAR worse luck with power supplies; I usually go through one of those every other year. Recently, ALL of the drives in my RAID 5 array (4x 120GB Seagate drives) as well as a fifth one (an identical Seagate 120GB that's standalone) started making noise at around the same time; of course I assumed there was some defect with this particular drive model.

    But thankfully, it turned out only to be my power supply (the +5V line would deliver +4.4V ~ +4.6V, while the +12V line would fluctuate between +11V and +13V). I can only conclude that Seagate drives are less tolerant than IBM/Hitachi's of power supply fluctuations, since I also have an old 80GB IBM/Hitachi Deskstar and a much newer 250GB SATA IBM/Hitachi drive, and neither batted an eye.

    Likewise, the system showed no other symptoms that pointed at the power supply; so a week or so ago, this post would have looked very different, with a few "F-You Seagate"'s thrown in there. :)

  5. S.M.A.R.T. by Anonymous Coward · · Score: 5, Informative

    I replace my hard drive when the S.M.A.R.T. info starts to signify problems, such as too many relocated sectors.

  6. Don't pre-emptively replace hard drives by Jerf · · Score: 5, Informative

    As I've already seen a couple of people say, don't preemptively replace your hard drives.

    Allow me to add: Here's why.

    Hardware failure rates follow a curve on average. They fail a lot after initial purchase, then slope down to their minimum after a couple of [relevant time periods] (probably "weeks" or "months" for hard drives, varies by what kind of thing it is), then slowly slopes upwards again.

    (Please do not miss the phrase "on average". Certain specific flaws can cause a certain product line to have unusual characteristics, like a sudden spike at six months or something. However, unless you somehow figure out a way to guess which hard drives are going to have such failures in six months when it's pretty amazing for the exact same hard drive to even be on the market for six months, the fact that these things can theoretically happen can't have much impact on your decisions. After all, if you knew that was going to happen, you'd just plain not buy the drive, period, regardless of the argument in this post.)

    Therefore, if you've got a "burned in" drive, you will be replacing a known-high-reliablility component with a component with a lower expected reliability. (I use "expected" in the probability/statistics sense here.) Unless you've discovered that you do have one of those funky products that all die in ten months, this is a bad move on average.

    I replace hard drives when they fail. I try to act as if they could die at any minute, although I fail.

    (But I try to get better. I'm in an all-laptop house, so it's difficult to have the convenience of an integrated backup solution and an automated, unforgettable script. However, with the recent Linux kernels finally supporting my SD card reader, I've gotten a high-capacity, slow, cheap SD card to stick in the previously-useless slot and I have an rsync now backing up the files I'd cry if I lost every hour. Sure, 1GB can't backup my entire system but most people's "cry if I lost it" datasets would fit into that. (Yes, there are exceptions... but if you're one of them, you've already got another back up solution in place, right? Right?))

  7. No need... No harddrive! by Bananatree3 · · Score: 4, Funny

    Running Knoppix on a dumb terminal with only a cd-rom drive, network card, motherboard, etc. without a harddrive, and then backing up everything onto a server over a broadband internet connection. Off site data center takes care of data backup, redundancy, etc. No mess!

  8. Never start replacing components by Heir+Of+The+Mess · · Score: 5, Funny

    I third that

    Never start replacing components unless it's the power supply or fans. Normally once my hardware starts screwing up I just sell the whole thing at a swapmeet as generally all the components will start all screwing up together.

    Err, good luck with your new machine.

    --
    Australian running a company that does C# / C++ / Java / SQL / Python / Mathematica