Re: RAID mirror, resyncing from bad disk

[Ronny Adsetts <ronny.adsetts@amazinginternet.com>]

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John Robinson said at 13/09/2009 21:24:
> On 13/09/2009 20:19, Ronny Adsetts wrote:
> [...]
>> The problematic array is /dev/md2 and the dying disk is /dev/sdc.
>>
>> When I try to resync it gets to about 99.2% then gives load of I/O
>> errors in /var/log/kern.log and finally gives up and restarts the sync.
>>
>> Ideally I just want to tell the system to ignore the bad sector and
>> just resync the array.
>>
>> Does anyone have any ideas on how I can get this resolved short of
>> reinstalling?
> 
> You need to ddrescue the contents of the dying drive onto a good one,
> then replace the dying drive with the fresh one. This will require
> taking the array down but you won't have to reinstall, unless you've
> lost something important in the lost sectors on the dying drive.

The bad sector is thankfully right at the end of the disk in an unallocated part of the LVM setup.

So, do I ddrescue the entire disk? I assume this will copy everything including the partition table and other gubbins?

Thanks very much, this looks like a winner to me. :-).

Ronny
-- 
Ronny Adsetts
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