This section covers the update of SAP systems with a high availability (HA) setup.

ZDO for SUM supports the update of high availability systems. The prerequisite is that the HA setup is set up correctly, that is, file systems such as DIR_PROFILE are also present on the bridge subsystem and are checked for functioning before starting the update. There are no further requirements for the HA system from ZDO side.

During the update with ZDO, a dialog in the phase SUM_ASK_ZDO_CONFIGURATION asks you whether you want to switch to HA maintenance mode for further execution. If you want to use this mode, and your system is installed with an HA switch-over environment, make sure that the failover capabilities of the cluster switch-over software are disabled in the target release during the cutover and rollback to the original system. The Software Update Manager stops for this in the phase REQ_USER_ROLLBACK_PREP.

For more information about how to prepare the ASCS instance for downtime, see the SUM 2.0 Guide. Navigate here to 6 Running the Software Update Manager    6.2 Actions During the Roadmap Steps    Preparing the ASCS Instance for the Downtime (HA Only).