Effect on backup

Since backups can occur only on the principal, you must take steps to ensure that you don't miss any scheduled backups due to failover. Establish a procedure to simultaneously initiate backups for both partners, but suppress the operation on the mirror.

To achieve this objective, first create a backup schedule for the principal.

Then take the following steps:

To simultaneously initiate backups for both partners

  1. Add the host that contains the mirroring partner to the client list of the policy that you created for the principal.

  2. Create a batch file on the mirroring partner that has the same name as the batch file specified in the backup selections policy.

    The batch file on the mirroring partner should be identical to the one used on the principal, with one exception. The value for SQLHOST and SQLINSTANCE are different.

    When you follow these steps, it ensures that any scheduled backup for a mirrored database is launched on both the principal and the mirror. The backup on the principal should run normally. The backup on the mirror is inhibited. You may notice that the NetBackup for SQL Server progress log for the inhibited operation specifies a message similar to the following:

    Database ACCOUNTING is in a mirroring role on SQL Server 
    instance SUN. This operation must be performed on  SQL Server 
    instance MOON.