VERITAS Storage Foundation 4.1 Intelligent Storage Provisioning Administrator's Guide

Implementing Off-Host Processing Solutions
96 VERITAS Storage Foundation ISP Administrator’s Guide
If a database spans more than one volume, you can specify all the volumes and their snapshot
volumes using one command, as shown in this example:
# vxsnap -g dbasedg make source=vol1/snapvol=snapvol1 \
source=vol2/snapvol=snapvol2 \
source=vol3/snapvol=snapvol3
Note This step sets up the snapshot volumes, and starts tracking changes to the original
volumes. When you are ready to create a replica database, proceed to step 3.
3. On the primary host, suspend updates to the volume that contains the database tables. The
database may have a hot backup mode that allows you to do this by temporarily suspending
writes to its tables.
4. On the primary host, refresh the plexes of the snapshot volume using the following command:
# vxsnap [-g diskgroup] refresh snapvol source=volume sync=yes
The sync=yes attribute starts a synchronization of the snapshot in the background.
For a database, multiple snapshots can be refreshed in parallel, as shown in this example:
# vxsnap -g dbasedg refresh snapvol1 source=vol1 snapvol2 \
source=vol2 snapvol3 source=vol3 sync=yes
5. On the primary host, if you temporarily suspended updates to the volume by a database in
step 3, release all the tables from hot backup mode.
6. The snapshot volume must be completely synchronized before you can move it into another
disk group. You can use the vxsnap syncwait command to wait for the synchronization to
complete as shown here:
# vxsnap -g volumedg syncwait snapvol
The vxsnap syncwait command exits with an exit code of zero when the snapshot volume
has been synchronized with the parent volume.
If required, you can use the following command to verify whether the
V_PFLAG_INCOMPLETE flag is set on a volume:
# vxprint [-g diskgroup] -F%incomplete snapvol
This command returns the value off if synchronization of the volume, snapvol, is complete;
otherwise, it returns the value on.
7. On the primary host, use the following command to split the clone storage pool containing the
snapshot volume into a separate disk group, snapvoldg, from the original disk group,
volumedg:
# vxdg split volumedg snapvoldg clonepool