Hi.. i had detached the mirror c1t1d0s6 from the zpool "zones".
When i tried to attach it back, the resilvering is done with the below output.
status: The pool is formatted using an older on-disk format. The pool can
still be used, but some features are unavailable.
action: Upgrade the pool using 'zpool upgrade'. Once this is done, the
pool will no longer be accessible on older software versions.
scrub: resilver completed after 0h22m with 0 errors on Wed Mar 7 08:09:17 2012
NAME STATE READ WRITE CKSUM
zones ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
c1t0d0s6 ONLINE 0 0 0 128K resilvered
c1t1d0s6 ONLINE 0 0 0 6.99G resilvered
# zpool list
NAME SIZE ALLOC FREE CAP HEALTH ALTROOT
san 405G 264G 141G 65% ONLINE -
zones 40G 6.99G 33.0G 17% ONLINE -
Is there something wrong here???
Nothing in that output worries me. The messages you are seeing about using an older format are documented at http://docs.oracle.com/cd/E23824_01/html/821-1448/gcikw.html#scrolltoc.
There is one thing to be careful of before upgrading zpool versions: if you have multiple boot environments and the Solaris version installed an older boot environment doesn't support the newer zpool version, that older BE will be unable to read the upgraded zpool. If that upgraded zpool is the root pool (i.e. "rpool" in most cases) you will be unable to boot using the old BE. That is, if you are now running Solaris 11/11 and your zones zpool was created with Solaris 11 Express or earlier, you should only upgrade the zpool version on the zones zpool if you no longer need to access it from Solaris 11 Express.