Backing up VOBs with vob_snapshot
The vob_snapshot utility automates snapshot backups.
About this task
- Back up the entire VOB storage directory, including any remote storage pools (see If the VOB has remote storage pools), as soon as possible after each vob_snapshot completes. You do not have to lock the VOB during this backup. If you complete this backup within 30 minutes of the time vob_snapshot completes, you are less likely to lose data when the VOB is restored. You can reduce backup time by excluding the VOB database (db directory) itself from the backup. (It has already been backed up by vob_snapshot.)
- Back up the snapshot itself. This is especially important if the snapshot is copied to a location on the same physical device as the VOB. If that device fails and the snapshot has not been backed up to other media or copied to a different device, the backup is useless.
Deferred deletion of source containers is enabled by the vob_snapshot_setup program and is intended to optimize chances that a pool backup that follows a vob_snapshot within 30 minutes will include all source containers to which the database snapshot holds a reference. When a container is replaced by new version data (for example, during checkin), the new container is created and the old one is deleted. If deferred deletion is enabled, the old container is added to a list of pending deletions and removed after 30 minutes.
Deferred deletion increases disk space requirements in a active VOB. On platforms running Linux® or the UNIX® system, you can run the kill –HUP command on the vob_server process to send deferred deletion statistics to its log file. When checkvob examines source pools, it reports any containers on the deferred deletion list. The deferred deletion list is written every five minutes to the file delete_list.db in the VOB storage directory.