I used the Microsoft article "How to install Exchange Server 2003 Service Pack 1 in a clustered Exchange environment" at http://www.support.microsoft.com/?kbid=867624 to guide me through applying Exchange Server 2003 Service Pack 1 (SP1) on the cluster nodes. Here are the basic steps I followed to apply the service pack:
- Apply the service pack to the passive node first and reboot the server.
- Take the Exchange services offline by using Cluster Administrator and move the virtual server to the node just updated.
- Right-click the group that contains the Exchange virtual server and choose Upgrade Exchange Virtual Server.
- Install the service pack on the other cluster node to complete the upgrade.