vob_snapshot_setup

An administrator uses vob_snapshot_setup modparam to apply the following snapshot parameters to each VOB or replica for which database snapshots are to be taken:

These parameters are combined to form a single string attribute of type vob_snapshot_parameters, which vob_snapshot_setup attaches to the VOB.

Here is how these parameters may appear in a vob_snapshot_setup lsvob –long listing:

For more information, see the –snap_to, –dbcheck, and –notify options.

The VOB snapshot backup/restore scenario requires additional disk space, both at restore time and during daily operation:

• At restore time, checkvob may require substantial disk space. See the checkvob reference page.
• Enabling VOB snapshots for a VOB also enables a deferred source container deletion mechanism, which typically increases source pool size. For a description of deferred deletion, see the Help.

Default

vob_snapshot_setup lsvob lists the VOB tag of each local VOB currently configured for database snapshot.

–short

Same as default.

–long

In addition to the VOB tag, vob_snapshot_setup lsvob lists each VOB's snapshot parameters and additional VOB identity details. If multiple VOBs use the same parent –snap_to directory, use the replica UUID returned by –long to find a particular snapshot in the parent directory.

vob-tag ...

Space-separated list of VOBs; restricts listing to one or more local VOBs.

Default

None. modparam and rmparam operations require a VOB tag argument.

vob-tag

The VOB's VOB tag, as specified in mkvob or mktag –vob.

Default

With modparam, you must specify a VOB tag; if you specify no other options or arguments, modparam prompts for all necessary input and displays explanatory text. If you specify both a VOB tag and a snapshot target directory, modparam does not prompt for additional parameters: vob_snapshot does not run the db_check operation, and the notify list is empty.

–snap_to snap-dir-pname

A disk location to store the snapshot. vob_snapshot appends the VOB's replica UUID to the –snap_to directory to create a subdirectory, then copies the VOB database to the subdirectory (after checking for sufficient disk space).

The replica UUID subdirectory that stores a VOB's database snapshot is overwritten the next time vob_snapshot processes that VOB.

Typically, the –snap_to directory gets backed up as part of normal backup operations some time after the snapshots are taken.

–dbcheck yes, –dbcheck no

Specifies whether to run the db_check utility on each snapshot.

vob_snapshot runs db_check to perform fundamental database consistency and integrity checks. (Later, at restore time, checkvob may examine the VOB database looking for ClearCase anomalies.) The db_check pass occurs after all snapshots are completed on the local host. Because this check can be time-consuming, it is disabled by default.

If vob_snapshot cannot lock the database and db_check is disabled, db_check runs on the snapshot at vob_restore time. Running db_check earlier, at snapshot time, may expose problems that you do not want to encounter at recover time.

–notify login-name[,...]

A list of user IDs to be notified when vob_snapshot processes this VOB or replica. This VOB-specific list supplements the per host notification list maintained in /var/adm/rational/clearcase/config/snapshot.conf. The snapshot.conf file also specifies the notification program to be used. If you do not want to supply a list of user IDs to be notified, specify –notify "''" on the command line.