1.10.3 Automatic Backup Service: csstored in Calendar Server
Version 6.3
When properly configured, the csstored service
creates automatic backups of the calendar database. You can configure Calendar
Server for automatic backups when the csconfigurator.sh configuration
program runs, or you can do it at a later time, as described in this guide.
If the service is started in the disabled state, it will send a message
to the administrator every 24 hours stating that automatic backups are not
enabled.
For instructions on how to configure this service to perform backups,
see Chapter 9, Configuring Automatic Backups (csstored).
When configured properly, the service has the following functionality:
-
Upon system start up and at 24 hour (default interval) intervals
thereafter, takes a snapshot of the live Calendar Server calendar database.
The interval is configurable. (If the service has been stopped and restarted,
it does not take another snapshot unless the configured interval has elapsed
since the last snapshot.)
-
Verifies the database by running csdb verify against
the backup copy.
If the verify step fails (the database is corrupted),
the service notifies the administrator. The administrator can put the live
database in read-only mode, allowing you to troubleshoot the problem without
having to shut down the databases. While in read-only mode, no modify or delete
transactions are accepted (no logging). For more information about read-only
mode, see 22.5.4 Preventing Service Interruptions When Your Database is Corrupted (Read-only Mode).
Administrator
intervention is required when a corruption is sensed. A notification is sent
to the administrator.
If the verify succeeds, csstored performs the
following additional tasks:
-
Creates an archival backup consisting of the database snapshot
and all the transaction log files that were applied to it since the previous
snapshot.
-
Creates a hot backup consisting of the database snapshot with
the transaction log files applied to it.
Should the live database
become corrupted, a hot backup provides an immediate up to date backup of
the database with a minimum of data loss and downtime.
For information
on how to restore an automatic backup copy, see 22.5.8 Restoring an Automatic Backup Copy.