Prior to releasing Exchange Server 2003 we didn’t test this scenario, and since we only support scenarios that we have tested and have confidence in this was considered unsupported. However, with so many customers interested in this method of upgrading we decided to test it and document the process. A KB article will be released describing the process, but for now here are the steps you need to know.
Summary: In some cases it may be preferable to do a clean install of the operating system or Exchange Server rather than upgrading. On a cluster, your existing Exchange 2000 virtual server can be preserved and upgraded even if you need to clean install Windows 2003/Exchange 2003. Some custom configuration may be lost using this method, we recommend performing a standard upgrade if at all possible. Please read and understand all the steps and issues thoroughly before beginning this upgrade process.
This kb article covers clusters that meet the following requirements:
Windows 2000 SP3
Exchange 2000 SP3
Steps: For this example I’ll run the EVS on node2 while I upgrade node1, but it doesn’t matter which node is upgraded first.
1. Evict the passive node and rebuild
Make sure the EVS and all cluster resources are all running on node2 (active node).
Use cluster admin from node2 to stop the cluster service on node1 and then evict it from the cluster.
On node1, format the disk and clean install W2k3.
Rejoin node1 to the cluster (Important! This must happen before running Exchange setup)
On node1, clean install E2k3.
2. Configure services
On node 1, run services.msc and set Distributed Transaction Service startup type to Manual
If you are using POP3 or IMAP set the start up type to manual on each service. (If you are not using these services consider deleting the resources and setting the services to disabled).
If you are using full text indexes please see the note below for special instructions.
On node2, take the Microsoft Exchange System Attendant resource offline (this will take all Exchange resources offline)
3. Upgrade the Exchange Virtual Server (EVS)
Move the offline EVS to rebuilt node (node1)
On node1, right click the System Attendant resource and select upgrade EVS
The upgraded EVS cannot be failed over to run on the older version node (node2). To prevent this from happening change the System Attendant resource possible owner list to include only the upgraded node.
Right click the System Attendant resource and select properties.
On the “general” tab next to “possible owners” click “modify”.
Under Possible owners select the name of the node that hasn’t been upgraded, and click the ? arrow button to remove it from the list.
Bring the EVS online
4. Repeat 1-2 (with node2 as the passive node)
Running Exchange setup on node2 should add it back to the possible owner list for the System Attendant resource
After both existing nodes are upgraded to Windows Server 2003 additional nodes can be added to the cluster.
Full Text Indexes begin a Full Population after upgrading the Exchange Virtual Server
After the cluster node has been upgraded to Exchange 2003, the Exchange Virtual Server has been upgraded, and the cluster resources come on-line, a full population will begin on all full-text indexes and the indexes will be disabled for searching. To avoid having the full population begin automatically, manually start and then pause a full or incremental population on all the full-text indexes on the server prior to upgrading the Exchange Virtual Server. If the indexes are already paused when you upgrade, they will remain paused and the upgrade will finish normally. After you have finished upgrading, you can manually resume building the indexes when it is convenient to do so. Once the indexes have been built, you can enable searching on the newly built indexes.
One Way Upgrade
Once an EVS is upgraded it cannot be run on a node with older versions of Windows and/or Exchange.
Other Applications Must Be Installed Again After Upgrade
Workflows, virus scanning, event sinks, and any other application installed on your existing server will need to be reinstalled and configured. Make sure all applications you are planning to bring forward are compatible with the newer versions of Windows and Exchange.
Customized Registry Keys Lost
Any feature that is enabled by setting a registry key (such as journaling) will not be carried forward with this upgrade. Any customization, performance tuning, manually set or altered registry key will not be persisted using this upgrade method. These will need to be manually reset.
No Active/Active support
Using this method of upgrading Active/Active clusters is not supported.
Risk of Downtime Increased by time between upgrading first and second nodes
Once the Exchange Virtual Server has been upgraded it cannot be run on the older version node. If anything happens to the upgraded node during this time, it has no passive node to fail to. To reduce the risk of downtime, upgrade the second node soon as possible after upgrading the first. The risk of downtime is increased the longer the EVS has only one node available to run on.