Hi I have two identical disks in a machine and have installed on c3d0 leaving c4d0 free.
paulj at opensolaris:~$ zpool status pool: rpool state: ONLINE 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: none requested config: NAME STATE READ WRITE CKSUM rpool ONLINE 0 0 0 c3d0s0 ONLINE 0 0 0 errors: No known data errors If I attempt to add the second disk to the zpool called 'rpool' paulj at opensolaris:~$ pfexec zpool attach rpool c3d0 c4d0 cannot label 'c4d0': EFI labeled devices are not supported on root pools. The -f option doesn't help. Could anyone give me a pointer please. Cheers Paul