Applies To: SQL Server
Used to determine if the current replica is the preferred backup replica.
Applies to: SQL Server (SQL Server 2012 through current version).
sys.fn_hadr_backup_is_preferred_replica ( 'dbname' )
Is the name of the database to be backed up. dbname is type sysname.
Returns 1 if the database on the current instance is on the preferred replica. Otherwise returns 0.
Use this function in a backup script to determine if the current database is on the replica that is preferred for backups. You can run a script on every availability replica. Each of these jobs looks at the same data to determine which job should run, so only one of the scheduled jobs actually proceeds to the backup stage. Sample code could be similar to the following.
If sys.fn_hadr_backup_is_preferred_replica( @dbname ) <> 1 BEGIN -- If this is not the preferred replica, exit (probably without error). END -- If this is the preferred replica, continue to do the backup.
The following example returns 1 if the current database is the preferred backup replica.
SELECT sys.fn_hadr_backup_is_preferred_replica ('TestDB'); GO
AlwaysOn Availability Groups Functions (Transact-SQL)
AlwaysOn Availability Groups (SQL Server)
CREATE AVAILABILITY GROUP (Transact-SQL)
ALTER AVAILABILITY GROUP (Transact-SQL)
Active Secondaries: Backup on Secondary Replicas (AlwaysOn Availability Groups)
AlwaysOn Availability Groups Catalog Views (Transact-SQL)