Platform Notes: Ultra 450 Workstation and Ultra Enterprise 450 Server

Preparing to Replace the Disk Drive

Back up your system.

Type su and your superuser password.

If possible, save the partition table for the disk you intend to replace.

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
```

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.

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
```

Detach submirrors.

If any slices of the disk are used by submirrors, the submirrors should be detached. For example:
```
# metadetach d20 d21
```

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
```

Terminate all other metadevice activity on the disk.

Check metastat output for other slices of the disk used by metadevices that cannot be detached (stripes not in mirrors, etc.). These metadevices must be unmounted if they contain file systems, or they must otherwise be taken off line.

Refer to the prtvtoc(1M) man page for more information.

Unmount any file systems on the disk.

Note -
If the file system(s) are on a disk that is failing or has failed, the umount operation may not complete. A large number of error messages may be displayed in the system console and in the /var directory during the umount operation. If the umount operation does not complete, you may have to restart the system.

For each file system returned, type:
```
 # umount filesystem
```

where filesystem is the first field for each line returned in Step 1.

For example:

# umount /export/home
# umount /export/home2

© 2010, Oracle Corporation and/or its affiliates