There are some installations that utilize a single node cluster hosting a clustered mailbox server for Exchange 2007.  It may become necessary to perform an upgrade of the solution to a different service pack.  This process can introduce some issues as the upgrade and upgrade processes assume that there is a second node in the cluster that can own both the cluster core resources and Exchange resources.

I wanted to outline a process that can be utilized to upgrade service packs on a single node cluster.

In order to being the upgrade process the clustered and Exchange services must be stopped.  This can be performed on the Exchange server by:

1)  Open an instance of Exchange Management Shell.

2)  Issue a stop-clusteredmailboxserver –identity <CMSName> –stopreason “Upgrade”

3)  Stop the cluster core resources group / cluster group.  Issue a cluster.exe group “cluster group” /offline.

4)  Exit the Exchange Management Shell

At this point the Exchange services will be stopped as well as the cluster core resources.  We should be able to begin the upgrade of the Exchange binaries at this time.  Use the following process to begin the Exchange upgrade.

The upgrade of the mailbox role binaries is completed by running this command from the service pack media:

setup.com /mode:upgrade

When the mailbox role upgrade has completed you can install any pending roll up updates.

The next step of the upgrade is to issue an upgrade to the clustered mailbox server.  To upgrade the clustered mailbox server:

1)  Start the cluster core resources by issuing the following command – cluster.exe group “cluster group” /online

2)  At this point the cluster core resources are online and cluster services should be started with the Exchange resources in an offline state (the same state prior to stopping the cluster services).

3)  Upgrade the clustered mailbox server by running the command - setup.com /uprgadeCMS.  When the command has completed the Exchange resources should be online on the node where the upgrade was performed.

These instructions were tested using Exchange 2007 SP1 on Windows 2008 single node Cluster Continuous Replication (CCR) installation.