How to bring a mirrored database online? -- Point to add to your DR Manual if you are using Mirroring

If you are using mirroring as DR solutions, you should consider adding below information in your manual to avoid any inconvenience during the recovery procedure:

If your principal and mirror servers are online and mirroring is working, then follow below procedure:

1. Connect to either partner.

2. Issue the following TSQL command:

ALTER DATABASE [mirrored_database_name] SET PARTNER OFF

If you lost your principal database and wants to bring mirrored database online, use following procedure:

Connect to partner and issue following TSQL command:

ALTER DATABASE [mirrored_database_name] SET PARTNER OFF

RESTORE DATABASE [mirrored_database_name] WITH RECOVERY;

Note: This will bring the mirrored database online as long as the mirrored database in not in synchronizing state. If the mirrored database is in synchronizing state and principal is not available, follow below procedure to bring mirrored database online:

a. Connect to the mirror server.

b. Issue following TSQL command:

ALTER DATABASE [mirrored_database_name] SET PARTNER OFF FORCE_SERVICE_ALLOW_DATA_LOSS
RESTORE DATABASE [mirrored_database_name] WITH RECOVERY;

This procedure will immediately bring the mirror online and break mirroring. However note that this approach must be used when there is absolutely no other option as this approach may cause data loss. For more details related to possibility of data loss, please visit at http://technet.microsoft.com/en-us/library/ms189977.aspx

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