How Often Do You Replace Your Hard Drives?

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?"

Comments

Uhh...

[Omeger]

When they break?

Re:Uhh...

[Anonymous Coward]

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.

One day too late

[Anonymous Coward]

One day too late

S.M.A.R.T.

[Anonymous Coward]

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

Don't pre-emptively replace hard drives

[Jerf]

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?))

Never start replacing components

[Heir Of The Mess]

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.