Updating Distributed and High Availability (HA) Systems

This section provides you with information about the update of distributed or high availability (HA) systems.

Context

Distributed Systems

The Software Update Manager is able to handle distributed configurations where your ASCS instance or other ABAP instances are installed on separate hosts as, for example, in a HA environment.

For heterogeneous systems, that is, systems that have different operating systems on the primary and additional application server instances, you have to perform manual actions. Provide at least the target kernel for the remote instances at the download directory. As a prerequisite, the SAP kernel directory of the system must follow the new layout (/usr/sap/<SID>/SYS/exe/uc/<platform>) and the SAP kernel replication with program sapcpe needs to be configured.

During the downtime, the Software Update Manager operates only with a local single-instance setup while all other instances are stopped. At this point of the update procedure, the Software Update Manager moves all the central services (enqueue service and message service) to the downtime instance. At the end of the downtime and before starting the productive system again, the original system setup will be restored and started afterwards.

High Availability Systems

The update of high availability systems differs from updates of distributed systems. Newer system offers the usage of the HA Maintenance Mode during upgrade, but for older systems there is still manual action required. For more information about updating your system in an HA environment, contact your HA solution implementation partner.

Maintenance Mode:

Before an update in a system environment with high availability, you must deactivate the HA solution for the clustered resources to prevent the HA software from interfering with the upgrade process. After the upgrade, the HA solution must be activated again. That is, the HA software must be told that maintenance mode must be switched on (deactivation of HA solution) or switched off (activation of HA solution) for an instance or the entire SAP system (without the database).

This can be carried out manually or automatically if the Software Update Manager supports the automatic execution of the deactivation and activation of the HA solution. The feature can be activated during the update by the selecting the checkbox Use of Maintenance Mode, if an availability check beforehand was successful. Note that you don't have to perform any manual steps such as starting or stopping instances and services, when you use this mode.

For more information about this feature and how to check whether the automatic maintenance mode is available, see SAP Note 2464065 Information published on SAP site .

Below, you find briefly outlined the update process for a high availability (HA) system.

Procedure

If necessary, you change your HA system configuration and clean up profiles.

For more information, see section Preparing the Update of Distributed and High Availability Systems.
You start the Software Update Manager.
The Software Update Manager checks the profile directory. If the ASCS instance is installed on a different host name, the tool assumes that the update is performed in a distributed or HA environment.
If prompted, you install a temporary license key in the shadow system and in the system during downtime. For information about license keys, see https://support.sap.com/licensekey

Note

The new temporary license will not be removed automatically after the update. You can delete the temporary license manually after the update. Prior to this, use transaction SLICENSE to check whether the old license still exists.
If you are running the ASCS instance on a separate host, and the operating system on this host is different from that on the primary application server instance, at the end of the downtime you are prompted to install the latest SAP kernel on the separate host with the ASCS instance.