no-reboot mirror creation

no-reboot mirror creation

[Rob Harris]

OK. Stupid question.

So, I have a 300G drive in my system, 'bout half full running jfs.

I added a second 300G drive because I want to do mirroring.

I don't have place to copy the data off to create a clean two-drive 
mirror from the get go, so I:

- created a one-drive mirror using mdadm (requiring --force) on the new disk
- mounted it
- copied the data over from the non-raid disk to the raid disk
- verified that all the data was copied
- changed the type of the partition on the old disk to FD
- # mdadm /dev/md1 --add /dev/hdf1 (added the newly created partition)

It seemed to work... kinda. It didn't actually add the partition to the 
mirror, but just set it as a spare; i.e. I never see it syncing the data 
from the old disk to the new.

Is there a way that I can add the drive to the mirror without setting it 
as a spare?

Thanks.
-R

Re: no-reboot mirror creation

[Laurent CARON]

Rob Harris wrote:
> OK. Stupid question.
> 
> So, I have a 300G drive in my system, 'bout half full running jfs.
> 
> I added a second 300G drive because I want to do mirroring.
> 
> I don't have place to copy the data off to create a clean two-drive 
> mirror from the get go, so I:
> 
> - created a one-drive mirror using mdadm (requiring --force) on the new 
> disk

you should have done

mdadm -Cv /dev/md0 -l1 -n2 /dev/XXX missing


> - mounted it
> - copied the data over from the non-raid disk to the raid disk
> - verified that all the data was copied
> - changed the type of the partition on the old disk to FD
> - # mdadm /dev/md1 --add /dev/hdf1 (added the newly created partition)
> 
> It seemed to work... kinda. It didn't actually add the partition to the 
> mirror, but just set it as a spare; i.e. I never see it syncing the data 
> from the old disk to the new.
> 
> Is there a way that I can add the drive to the mirror without setting it 
> as a spare?
> 
> Thanks.
> -R
> 
> -
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Re: no-reboot mirror creation

[Rob Harris]

KELEMEN Peter wrote:
> * Rob Harris (rharris@shabadoo.org) [20060328 09:08]:
> 
>> - created a one-drive mirror using mdadm (requiring --force) on
>> the new disk
> 
> Repeat the exercise, but create a two-drive mirror with one of the
> disks missing.
> 
> 	mdadm -C /dev/mdX -l1 -n2 missing /dev/XXX
> 

Thanks all--I figured it out.

Actually, I just failed and removed the drive that was added as a spare, 
then did:

mdadm /dev/md1 --grow -n2
mdadm /dev/md1 --add /dev/hde1

It's happily resyncing right now. Thanks again!
-R