[linux-lvm] [Q] LVM snapshot volume extendable?

["Sean Oh" <oh@storageone.co.kr>]

Hi

I am using LVM 1.0.6, kernel 2.4.20 and XFS (from linux-2.4-xfs CVS).

My question is that is the snapshot volume extendable?

My environment is as follows:

/dev/vg01/lv01 ---> XFS, 2G
/dev/vg01/lv01_snap --> 256M, snapshot for /dev/vg01/lv01, mounted under
/snap with ro,nouuid,usrquota,grpquota,noatime

Now I have wrote a small shell scripts that if lv01_snap is more than 50%
full, automatically increase the lv01_snap. But it seems to me that it does
not work well..

What I did in the shell scripts are 'lvextend -L+256M /dev/vg01/lv01_snap'
with/without 'xfs_growfs /snap'.

After umounting the /snap and trying to remount /snap, it complaints as
below

XFS: recovery required required on read-only device
XFS: write access unavailabe, cannot proceed
XFS: log mount/recovery failed
XFS: log mount failed
mount: wrong fs type, bad option, bad superblock on /dev/vg01/lv01,
       or too many mounted file systems
       (aren't you trying to mount an extended partition,
       instead of some logical partition inside?)

BTW, extending the original lv01 works fine with lvextend and xfs_growfs.

Could someone please help?

Thanks in advance