Managing Serviceguard Extension for SAP, December 2007

SGeSAP Cluster Administration
Change Management
Chapter 6 303
Within the CCMS you can define operation modes for SAP instances. An
operation mode defines a resource configuration. It can be used to
determine which instances are started and stopped and how the
individual services are allocated for each instance in the configuration.
An instance definition for a particular operation mode consists of the
number and types of Work processes as well as Start and Instance
Profiles. When defining an instance for an operation mode you need to
enter the hostname and the system number of the application server. By
using relocatable names to fill in the hostname field, the instance will be
working under control of the CCMS after a failover without a change.
NOTE If an instance is running on the standby node in normal operation and is
stopped during the switchover
Only configure the update service on a node for Application Services
running on the same node. As a result, the remaining servers, running
on different nodes, are not affected by the outage of the update server.
However, if the update server is configured to be responsible for
application servers running on different nodes, any failure of the update
server leads to subsequent outages at these nodes. Configure the update
server on a clustered instance. Using local update servers should only be
considered, if performance issues require it.