The metassist command checks disks to see which disks appear to be unused, and attempts to conservatively determine which disks are available. Any disk or slice that is determined to be in use is considered unavailable for use by the metassist command. Key checks include:
Disks used in other disk sets
Slices with a file system superblock, indicating a mountable file system
Slices used in other Solaris Volume Manager volumes
Any slices that meet these criteria are unavailable for use by the metassist command.