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Re: [LUG] Hard drive formatting

 

On 15/07/12 00:30, Simon Waters wrote:
On 14/07/12 13:00, George Parker wrote:
    I have a 500 Gb hard drive, not very old, that has a few bad blocks
that are causing me grief.
As Neil says the badblocks documentation says what to do.

More crucially it also tells you that you probably don't want to do it.

It may not be "just a few bad blocks", since a few bad blocks are
handled by the disk drive when it is first used.

It is probably a few blocks that have deteriorated since you wrote data
to do. Or more bad blocks than the automatic disk sparing has reserved.

The "dd" trick is that the disk drive will automatically swap out
badblocks when it encounters them, so writing to all the blocks
typically forces the drive to swap out any badblocks it encounters on
writing. So yes the blocks are still on disk, but the disk firmware will
know not to use them.

Basically if you encounter bad blocks in normal operation of a disk toss
it, or use it for something where the data doesn't matter (caching, or
similar - but appreciate bad reads can cause the OS to crash).

If it is reasonably new just return it to vendor under warranty. They
likely have a protocol to follow, usually the manufacturer handles it
although the law says it is the vendors responsibility to resolve it.

  Simon


Thanks to all. Simon, there is nowhere I have found that says DD swaps out bad blocks when you write. I did do this however and reinstalled from scratch but the installer crashed very near the end saying it had trouble copying to disk. The distro (Mint 13) did boot up but it was very flakey.

When I say it is a new drive I mean maybe 5 years old so I have thrown in the towel and bought a new one. The old one can join the other kit in the attic until my Yorkshire soul allows me to get rid after a suitable period of mourning.

Thanks again everyone

George


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