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

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Use the following command to make a full-sized snapshot, snapvol, of the
tablespace volume by breaking off plexes from the original volume:
# vxsnap -g volumedg make \
source=volume/newvol=snapvol/nmirror=N
The nmirror attribute specifies the number of mirrors, N, in the snapshot
volume.
If the volume does not have any available plexes, or its 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/nmirror=2 \
source=vol2/snapvol=svol2/nmirror=2 \
source=vol3/snapvol=svol3/nmirror=2
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
See the section “Creating a Share Cache Object” in the “Administering Volume
Snapshots” chapter of the Veritas Volume Manager Administrator’s Guide
for more information.
181Decision support
Creating a replica database on the same host