Requirements (Server Clusters: Rolling Upgrades. Upgrading to Windows Server 2003)

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Rolling upgrade from Windows 2000 to Windows Server 2003

To perform a rolling upgrade of the operating system to Windows Server 2003 operating system on cluster nodes, you must start with Windows 2000 Advanced server (including any service packs for example SP1, SP2 etc) or Datacenter Server. Windows Server 2003 operating system does not support rolling upgrade from earlier Windows operating system, for example Windows NT 4.0.
You can perform rolling upgrade from Windows 2000 Advanced Server to Windows Server 2003 Enterprise Edition.
You can perform rolling upgrade from Windows 2000 Datacenter Server to Windows Server 2003 Datacenter Edition.

Perform rolling upgrade to Windows 2000 Advanced Server first, then to Windows Server 2003 Enterprise Edition.
Perform a non-rolling upgrade directly from Windows NT 4.0 to Windows Server 2003 Enterprise Edition, which will not allow you to maintain cluster availability.

A rolling upgrade can be used to upgrade Windows NT 4.0 Server, Enterprise Edition SP4 to SP5, SP5 to SP6, and so forth. It can also be used to upgrade any Enterprise Edition service pack later than SP3 to Windows 2000 Advanced Server.
Upgrades from Windows NT 4.0 to Windows 2000 Datacenter Server are not supported. Windows 2000 Datacenter Server can be installed in a clean install process only.

A rolling upgrade from any version of Windows Server 2003 (64-bit) Enterprise Edition LE release to Windows Server 2003 (64-bit) Enterprise Edition is not supported. You will have to perform either a fresh install or upgrade of your system to Windows Server 2003 (64-bit) Enterprise Edition. This mean the cluster will not be available during upgrade/installation.