Explanation

This happens to a disk which has a inode error on the OS disk.
The SA wants to do a fsck but afraid the it might cause unpredictable error on the disks. (Well,
i dont think this is really necessary, but the user requested for it)
This machine has the boot disks encapsulated and mirrored. First we want to know the mirrored disk's plex. The mirrored disk is c2t1d0. You can see the purpose is to break mirror and boot up onmirrored disk to perform a fsck on mirrored disk. When it's done, boot up from root disk and
reattach the mirror.