Backing Up an Exchange Server 2003 Cluster's Shared Disk Resources


Topic Last Modified: 2006-01-16

The shared disks in an Exchange 2003 server cluster are a critical part of the cluster technology. An Exchange server cluster's shared disk resources can include the quorum disk resource and the resource that contains the Exchange databases and transaction log files. Any node in a server cluster can access the shared disks while the cluster service is running, and all the nodes rely on those disks to be intact. If a cluster's shared disk fails, any new node that joins that cluster will not be able to access the data that is stored on the failed shared disk.

If you plan to use the "restore the server" method to recover your shared disk resources, do not include the drives for those resources in your full computer backup set. To back up the Exchange databases and log files on your server cluster's shared disks, create a separate backup set by using the Microsoft Information Store option in Backup. To back up your quorum disk resource, perform either a full computer backup or a Windows backup of the node that currently owns the quorum disk resource. Make sure that you include the System State data together with the boot and Windows partitions of the node.

When you create backup sets of your cluster node that contains a server cluster's shared disk, back up any dynamic data that exists on that disk.

If you are not using Majority Node Sets, the quorum disk resource maintains the consistency of your server cluster by recording the changes that have been made to the cluster database. Each node in the cluster has access to the most recent database changes. The cluster database contains information about all physical and logical elements in a server cluster, including cluster resource object properties and configuration data. The quorum disk resource uses the quorum log file (Quolog.log), to make sure that the cluster registries on all nodes of the server cluster are consistent with each other. The cluster registry for each node is located in the %systemroot%\Cluster\CLUSDB directory of each node.

Create a separate cluster group for your quorum disk resource, and keep it on its own physical hard disk.

Quorum disk resource files are located in the /MSCS folder of the drive that contains the quorum disk resource. When you back up the quorum disk resource, the following files are also backed up.

Quorum disk resource files to back up

File type Definition


The shadow copy files of the cluster registry.


The quorum log file.

<GUID of resource>\*.cpt

The registry checkpoint files for the resource identified by the GUID.

<GUID of resource>\*.cpr

The crypto checkpoint files for the resource identified by the GUID.


The file that indicates that a backup is completed (a read-only, hidden, 0-byte file).

Whenever the System State data is backed up on the node in the server cluster that currently owns the quorum disk, quorum disk resource data is also backed up. Therefore, to back up the quorum disk resource data, you can create either a full computer backup set or a Windows backup set for that node. Both of these backup sets include a backup of System State data.

You only have to back up the node in the server cluster that currently owns the quorum disk resource. If you lose the whole cluster, you can recover the first node and the quorum disk resource that it controls. After that node is running, you can insert new nodes into the cluster. For a full cluster recovery, you can create and restore backups for all the nodes. It is recommended that you label the backup that contains the quorum disk resource. If you must rebuild a whole server cluster, you must restore the node that owned the quorum disk resources before you restore or join any other node. When you make sure to first restore the node that owned the quorum disk resource, you ensure that the cluster resource objects in the cluster are restored before you reintroduce any other nodes to the cluster.