If any drives containing database files or transaction log files are lost, you must use your Exchange database backups to recover those drives. To restore a backup of the Exchange cluster node databases, you must perform steps that are similar to the steps for restoring Exchange databases to a stand-alone member server.

The only difference between these processes is that, when you restore the cluster node databases, you use the Network Name resource of the Exchange Virtual Server (EVS) computer instead of the Windows computer name of the cluster node. You must type the Network Name of the EVS in the Restore text box of the backup utility (Backup) in Windows Server 2003. The Network Name of the virtual server is the same name that users use to connect to their EVS that is running in the cluster. If you have the correct permissions, you can back up and restore the Exchange databases of an EVS from any node in the cluster, or from any computer in the domain that is configured to perform Exchange backup and restore procedures. For detailed information about how to restore Exchange databases, see "Restoring Exchange Mailbox or Public Folder Stores."

The quorum disk resource is a shared disk resource that contains details of all the changes that have been applied to the cluster database. The quorum disk resource is accessible to other cluster resources. Therefore, if one node fails over to another, all cluster nodes have access to the most recent database changes.

If the drive that contains the quorum disk resource is damaged, you can use several methods to restore it. For more information, see the Windows Server 2003 online Help and Microsoft Knowledge Base article 245762, "Recovering from a lost or corrupted quorum log."