• Please see if these steps are good to follow:

    STEPS: (SP upgrade - 2005 Cluster)

    1.) Move both instances on one node (if active/active)

    2.) Run the patch files from active node

     Installer automatically upgrade passive node first and then active.

    3.) After installation reboot the passive node.

    4.) Once passive node came online than failover the instance on that node

    5.) Reboot the other node.

    6.) At the end failback the instances as per the previous set up