VERITAS Volume Manager 3.5 Migration Guide (August 2002)

Converting LVM Volume Groups to VxVM Disk Groups Final 24 July 2002

16 VERITAS Volume Manager Migration Guide

Be sure to use the -f option to save the data into a ﬁle other than the default.

vxvmconvert uses LVM utilities which themselves save the conﬁguration using

vgcfgbackup. If you do not use the -f option when you attempt to backup the

conﬁguration, the conversion process will overwrite your attempted backup.

A copy of this LVM conﬁguration should be kept off-line on tape or some other medium

for use in the event of a disaster during conversion.

For example, to put a copy on tape, use the following command:

# tar cvf /dev/rmt/c3t0d0BEST /vgbackups/vg08

Note The vxvmconvert utility itself also saves a snapshot of the LVM metadata in the

process of conversion for each disk. This data is saved in a different format from

that of vgcfgbackup. It can only be used via the vxvmconvert program. With

certain limitations, you can reinstate the LVM volumes after they have been

converted to VxVM using this data. (See section “Example: displaying the

vxvmconvert menu”.) Even though vxvmconvert provides this level of backup

of the LVM conﬁguration, you are advised to use vgcfgbackup before running

vxvmconvert.

Backing up user data

To back up user data, use your regular backup processes.

Caution Before you do the backup, you should carefully review “step 9. Implementing

changes for new VxVM logical volume names.” Backup processes and systems

themselves may have dependencies on the volume names currently in use on

your system. The conversion to VxVM changes those names. You are advised to

understand theimplications name changeshave for restoring from the backups

you are about to make.

File system back up of user data

You can use the backup utility that you normally use to back up data on your logical

volumes. For example, to back up logical volumes that contain ﬁle systems, the

fbackup(1M) command can be used to back up the data to tape.

For example, to backup the data on /dev/vg01/lvol3 mounted on /foodir, use the

following command:

# fbackup -0i /foodir -f /dev/rmt/c0t0d0BEST