Omniback Database Maintenance

Omniback Database Maintenance

HP recommends that maintenance be done on a regular basis in order to keep the OBDB running smoothly. The following explains the purging process. I feel that if you follow the process below, you will not have to increase the size of your database file (fnames.dat). The default size is 2GB and can be increased to 8GB in 2GB increments. First you should check to see if the file system is full by typing: “bdf var”. Then check to see if the database is full by typing:

/opt/omni/sbin/omnidbutil -extendinfo

If the database is full, you can extend the database by typing:

omnidbutil -extend {pathname} -maxsize {size}

You can either run a manual purge or schedule an automatic purge of the OmniBack database. Purging the database will not shrink the size of the database; you only make space available for new information. Manual purge using the omnidbutil command

omnidbutil -purge [-detail] [-days NumberOfDays ]

removes all obsolete file versions from database. If NumberDays is specified, purge also removes all failed/aborted backup sessions (for which there are no valid media) and restore sessions older than NumberDays days. NumberDays must be greater than zero. If -detail option is specified, purge also removes obsolete file.

When run manually, the omnidbutil -purge command will return to the prompt immediately. This does not indicate that the purge process has ended. An actual purge process called “psm” has been started and you can monitor the status of the purge by viewing the /var/opt/omni/log/purge.log file.

An example of what this file contains:

02/01/00 12:00:00 PSM.2858.0 ["/src/db/adm/purge.c/main/46":956] A.03.10b325
[[[ Purge session started ]]]]

02/01/00 12:00:00 PSM.2858.0 ["/src/dB/adm/purge.c/main/46":729] A.03.10b325
[Deleting file versions][entry]

02/01/00 12:00:12 PSM.2858.0 ["/src/dB/adm/purge.c/main/46":1027] A.03.10b325
[REPORT_DATA] 949435200 949435212 120 0 0 0 0

Sometimes, a purge process may seem to take a very long time. By default, OmniBack has the global variable DBPurgeSuspension set to 1 which means that a purge session will be suspended whenever a backup or restore session is in progress. You can change this value in the global file, but setting it to 0 will mean that the purge process will run in parallel with the backup or restore session. This could have a potential impact on performance.

To stop a purge process, use the following command:

omnidbutil -purge_stop

Use purge_stop option to stop a running purge session.

Note:This command only sends a stop request to the purge session manager. Response may not be immediate. Do not kill the purge process using the kill command.

To check to see if a purge process is running, type “omnistat” without arguments.
If there is a purge session in progress, you will see output similar to:

SessionID Type Status User

R-2000/02/01-29 Purge In Progress root.sys@cosmo.rose.hp.com

Automatic purge using a schedule

Scheduling an OmniBack database purge is different in OmniBack 2.55 and OmniBack 3.x. By default, the purge process runs at 12 noon every day.

For OmniBack 2.55, you can change the purge schedule by editing the following variable in the /etc/opt/omni/options/global file.

# DBPurgeStartTime="WD1 HH1 .. WD7 HH7"
# DBPurgeStartTime="-1"
DBPurgeStartTime="0 15 1 15 2 15 3 15 4 15 5 15 6 15"
# default: "0 12 1 12 2 12 3 12 4 12 5 12 6 12"
# Specify purge session start times in the following format:
# "week_day_1 hour_1 week_day_2 hour_2 ... week_day_n hour_n".
# The day of the week is 0-6, 0=Sunday. To prevent a purge
# session from running at all, specify "-1".

The above example will start the purge at 15:00 hours (3:00 p.m.) every day of the week.

OmniBack 3.x no longer uses this global variable for purge scheduling. Instead, it uses the /etc/opt/omni/purge_schedule file for HP-UX and %OMNIBACK_HOME%configpurge_schedule on NT where %OMNIBACK_HOME% is the location where OmniBack was installed – e.g. C:Program FilesOmniBack.

Since the syntax for this file is not obvious, it is recommended to use the Windows interface to change the purge schedule:

• * Open up the OmniBack Manager GUI
• * Select the OmniBack Database context
• * Click on the Purge Schedule folder.
• * To clear the current schedule, click on “Reset”.
• * Click on “Add” to create a new schedule. This will bring up a sub-window in which you can specify specific purge options such as: recurring and type of purge (e.g. full or standard).
  o A Full Purge purges obsolete file names and file versions.
  o A Standard Purge purges obsolete file versions only.

• * When done, click on “Apply”

Once you have created the schedule, you can check the format of the file and use this to create the actual schedule file on the UNIX Cell manager.

If running the purge command manually or automatically, you can specify the “-days” option. If you specify a number of days, this will instruct the purge process to remove aborted sessions that are older than the number of days you have specified as well as aborted sessions that are older than the number of days you have specified. To specify this option for an automatic purge, modify the “DBPurgeOptions” global file parameter:

# DBPurgeOptions=-days xx -detail

# default: ""
# Specify database purge options. Aborted sessions and restore
# sessions older that xx days are removed, if -days xx is
# present. Specify -detail to purge obsolete files.

Note that this global option is no longer valid for OmniBack II 3.x.