SQL Server 2012
Specifies how replicas in the primary role are treated in the evaluation to pick the desired replica to perform a backup.
Assembly: Microsoft.SqlServer.SqlEnum (in Microsoft.SqlServer.SqlEnum.dll)
|No preference is stated for backup on replicas based on its current role. Only BackupPriority and online/connected states will be considered for replica choice.|
|Backups occur only on the primary replica, wherever it is.|
|Backups occur on the secondary replicas, except when the primary replica is the only replica online.|
|Backups occur only on the secondary replicas. If no secondary replicas are online, backup will not be performed.|
|The desired replica to perform a backup is unknown.|