Sun Microsystems Ultra 450 Manual page 33

If the disk label can still be read, save the disk partitioning at this time.
Note - Save all the disk partitioning information immediately after configuring
metadevices or file systems for use when recovering from device failure later.
Use the prtvtoc command to save the partition information.
# prtvtoc /dev/rdsk/cwtxdys0
> saved_partition_table_file
For example:
# prtvtoc /dev/rdsk/c1t2d0s0 > /etc/c1t2d0s0.vtoc
4. Identify metadevices or applications using the device you plan to remove.
For example:
# metadb | grep c1t2d0
# metastat | grep c1t2d0
# mount | grep c1t2d0
Save the output of the commands to reconstruct the metadevice configuration
after you replace the disk.
5. Delete database replicas.
If there are database replicas on the disk, these must be deleted. First record the
size and number of database replicas on each slice; then delete them.
# metadb -d cwtxdysz
For example:
# metadb -d c1t2d0s0
6. Detach submirrors.
If any slices of the disk are used by submirrors, the submirrors should be
detached. For example:
# metadetach d20 d21
7. Delete hotspares.
If any slices are used by hotspare pools, remove them. Record the hotspare pools
containing the slices; then delete them. For example:
# metahs -d all c1t2d0s1
Disk Drive Hot-Plug Procedures
25