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

Removing a cache
To remove a cache completely, including the cache object, its cache volume and all
space-optimized snapshots that use the cache:
1
Run the following command to find out the names of the top-level snapshot
volumes that are configured on the cache object:
# vxprint -g diskgroup -vne \
"v_plex.pl_subdisk.sd_dm_name ~ /cache_object/"
where cache_object is the name of the cache object.
2
Remove all the top-level snapshots and their dependent snapshots (this can
be done with a single command):
# vxedit -g diskgroup -r rm snapvol ...
where snapvol is the name of a top-level snapshot volume.
3
Stop the cache object:
# vxcache -g diskgroup stop cache_object
4
Finally, remove the cache object and its cache volume:
# vxedit -g diskgroup -r rm cache_object
Creating traditional third-mirror break-off snapshots
VxVM provides third-mirror break-off snapshot images of volume devices using
vxassist and other commands.
To enhance the efficiency and usability of volume snapshots, turn on FastResync.
See the Veritas Volume Manager Administrator's Guide.
If Persistent FastResync is required, you must associate a version 0 DCO with the
volume.
See “Adding a version 0 DCO and DCO volume” on page 253.
A plex is required that is large enough to store the complete contents of the volume.
Alternatively, you can use space-optimized instant snapshots.
The recommended approach to performing volume backup from the command
line, or from a script, is to use the vxsnap command. The vxassist snapstart,
snapwait, and snapshot commands are supported for backward compatibility.
The vxassist snapshot procedure consists of two steps:
Administering volume snapshots
Creating traditional third-mirror break-off snapshots
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