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

# vxsnap -g volumedg addmir volume [nmirror=N] \
[alloc=storage_attributes]
# vxsnap -g volumedg make \
source=volume/newvol=snapvol[/nmirror=N]\
[alloc=storage_attributes]
By default, one snapshot plex is added unless you specify a number using the
nmirror attribute. For a backup, you should usually only require one plex.
You can specify storage attributes (such as a list of disks) to determine where
the plexes are created.
If the volume layout does not support plex break-off, prepare an empty volume
for the snapshot.
See “Creating a volume for use as a full-sized instant snapshot” on page 150.
Then use the following command to create the snapshot:
# vxsnap -g volumedg make source=volume/snapvol=snapvol
If a database spans more than one volume, specify all the volumes and their
snapshot volumes as separate tuples on the same line, for example:
# vxsnap -g dbasedg make source=vol1/snapvol=svol1 \
source=vol2/newvol=svol2 source=vol3/snapvol=svol3
If you want to save disk space, you can use the following command to create
a space-optimized snapshot instead:
# vxsnap -g volumedg make \
source=volume/newvol=snapvol/cache=cacheobject
The argument cacheobject is the name of a pre-existing cache that you have
created in the disk group for use with space-optimized snapshots.
See “Creating a shared cache object” on page 151.
If several space-optimized snapshots are to be created at the same time, these
can all specify the same cache object as shown in this example:
# vxsnap -g dbasedg make \
source=vol1/newvol=svol1/cache=dbaseco \
source=vol2/newvol=svol2/cache=dbaseco \
source=vol3/newvol=svol3/cache=dbaseco
Note: This step sets up the snapshot volumes ready for the backup cycle, and
starts tracking changes to the original volumes.
Online database backup
Making a backup of an online database on the same host
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