At 09:25 9-4-2004 +0100, Colin Guthrie wrote:
>Hi there,
>
>I saw your post on http://oss.sgi.com/archives/linux-xfs/2003-01/msg00300.html
>
>I have just done exactly the same thing.
>
>I have backups of the most important files that are on the raid array, but
>I simply don't have the space for a full backup.
>Anyway, I got very close to the end of my array before raidreconf borked
>on me.
This happened to you as well?
>I was just wondering how to acheive the following bit:
><QUOTE>
>Because this happened with just one hash mark to go I ad some hope that
>the filesystem would be mostly intact. The process already ran for about 2
>hours. I recreated the /dev/md0 array with the new raidtab and it started
>resyncing.
></QUOTE>
>
>How to I "recreate the /dev/md0 array witht he new raidtab?"
>
>I'm guessing it will be a mkraid /dev/md0 with some form of switch or two,
>but when I type "mkraid --really-force --upgrade /dev/md0" I get a dire
>warning about detroying all data.
I used mkraid --force with the new raidtab. Because the array was nearly
done reconfiguring the array is actually closer to the new configuration
then the old one. That is why you should recreate it in this case with the
new config.
Using mkraid on an existing array is really dangerous if the configuration
you are writing is not identical to the existing configuration. In this
case alsmost all data is allready reconfigured.
If you recreate the array with the new configuration it will start
resyncing the on disk data according to the new configuration. Raidreconf
also moves the parity bits around to the new configuration so it will
basically force a rebuild of the array in the "correct" configuration and
thus no data will be lost.
*However* if there is data which was not yet moved around by raidreconf
this data will be incorrectly rebuilt using the new raid configuration and
as such will be lost. For my case it involved just a few files and I got lucky.
>Is there anyway to run mkraid (and perhaps the --upgrade switch is wrong,
>it's really for kernel upgrades) without it destroying the data currently
>on the raid?
--upgrade probably will not work.
>Many thanks for your insight.
Cheers
--
Seth
I don't make sense, I don't pretend to either. Questions?
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