Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

During a conversion, any spurious reboots, power outages, hardware errors or
operating system bugs can have unpredictable and undesirable consequences.
You are advised to be on guard against disaster with a set of verified backups.
Backing up an LVM configuration
Use the vgcfgbackup(1M) utility before running vxvmconvert to save a copy of
the LVM configuration.
You can back up the LVM volumes using the following command:
# vgcfgbackup -f pathname/filename vol_grp_name
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 back up the
configuration, the conversion process overwrites your attempted backup.
Keep a copy of this LVM configuration offline 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 by the vxvmconvert program. With
certain limitations, you can reinstate the LVM volumes after they have been
converted to VxVM using this data. Even though vxvmconvert provides this level
of backup of the LVM configuration, you are advised to use vgcfgbackup before
running vxvmconvert.
See “Example: displaying the vxvmconvert menu” on page 417.
Backing up user data
To back up user data, use your regular backup processes.
Warning: Before you do the backup, you should carefully review how to implement
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 the implications name changes have for restoring from the backups
you are about to make.
Offline data migration
Converting LVM to VxVM
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