Different disk size LVM root mirroring

[S.K. Chan]

Just need a quick confirmation. I got a 9GB root disk mirrored to another same 9GB disk. The mirrored disk is bad (got stale extents). Can I use an 18GB disk to replace it ?

[Helen French · Accepted solution]

Hi S.K,

Yes I think you can use it ( not tried). But the size of lv's will remain same !

HTH,
Shiju

[Patrick Wallek]

Yes, this should work.

You will probably on "see" 9GB of the 18GB on the new disk due to the "Max PE per PV" parameter, but you probably don't care about that at this point.

You should be able to replace the bad disk, do a vgcfgrestore and then vgsync and you should be fully mirrored again.

[Paula J Frazer-Campbell]

Hi
Yes it will work but as already stated it will only see 9 gig.

A mismatch of disks in a mirrored environment will slow the system down as one disk waits for the other.

Best option install the 18 gig - mirror - break the 9 gig out of the mirror and replace with another 18 gig of same spec.

HTH

Paula

[fg_1]

SK

You can use an 18GB to replace the 9GB in the mirror, only 9GB will be seen by the mirror.

Other than that, no problem.

GL.
FG

[pap]

Hello,
You can definately use 18 GB drive for mirroring. Not a problem in that. The worst thing is that you will loose 9 GB of space on that disk. Only 9GB size will be effective for this disk.

You can have an option in future.
Right now do mirroring with 18GB disk and later when you decide to replace existing disk of 9GB (Original root Disk) by 18GB , you can do it.

Then you will have both 18GB drives mirrored.

Thanks,

-Piyush.