How to Restore a Microsoft SQL Server Master Database

Applies to…

  • DxEnterprise
  • Microsoft SQL Server

Summary

Restoring the Microsoft SQL Server master database running on a DxEnterprise cluster.

Information

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:

  1. Freeze the VHost before restoring master.
  2. Unfreeze the VHost after restoring master.

The following is a general procedure that you can use to restore the master database:

  1. Remote Desktop into the active node that is currently hosting the instance.
  2. Connect DxAdmin.
  3. Right-click on the active node under the VHost and select “Freeze virtual host on node”.
  4. Windows – Open Regedit and browse to the instance key (e.g. HKLM\Software\Microsoft\Microsoft SQL Server\\MSSQLServer\Parameters) and add SQLArg3 with string value of “-m”.
    Linux – Launch mssql-server with the -m parameter (e.g. /opt/mssql/bin/sqlservr -m).
    This puts the instance under single-user startup mode so you can restore master. Restart the instance service to take effect.
  5. Restore master database. See http://msdn.microsoft.com/en-us/library/ms190679(v=sql.105).aspx for additional info.
  6. Once master is restored, again using Regedit (Windows only) to remove the single-user startup parameter. Restart the instance service to take effect.
  7. In DxAdmin, right-click on the frozen node under the VHost and select “Unfreeze virtual host” to put the VHost back into normal operation again.