Restore a Microsoft SQL Server Master Database
Restoring the Microsoft SQL Server master database running on a DxEnterprise cluster.
This is very much the same as how you would do so with a stand-alone instance. There are really just two additional steps you need to take to successfully restore a master database:
Freeze the Vhost before restoring master.
Unfreeze the Vhost after restoring master.
The following is a general procedure that you can use to restore the master database:
Remote Desktop into the active node that is currently hosting the instance.
Right-click on the Vhost and select Freeze virtual host on node.
Start the instance in single-user startup mode so that master can be restored.
Windows - Open Regedit and browse to the instance key
HKLM\Software\Microsoft\Microsoft SQL Server\MSSQLServer\Parametersand add SQLArg3 with string value of “-m”. Restart the instance service for the changes to take effect.
Linux - Launch mssql-server with the -m parameter
Restore master database. See How to: Restore the master Database (Transact-SQL) for additional information.
Once master is restored, use Regedit (Windows only) to remove the single-user startup parameter. Restart the instance service for the changes to take effect.
In DxAdmin, right-click on the Vhost and select Unfreeze virtual host to put the Vhost back into normal operation again.