Managing Serviceguard Extension for SAP on Linux (IA64 Integrity and x86_64), February 2008

Step-by-Step Cluster Conversion
SAP WAS System Configuration
Chapter 3 179
IS1180 Installation Step:
Within the SAP Computing Center Management System (CCMS) you
can define operation modes for SAP instances.
An operation mode defines a resource configuration for the instances in
your SAP system. 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 consist of the
number and types of work processes as well as start and instance profiles
(starting with version 3.0 the CCMS allows profile maintenance from
within the SAP system).
When defining an instance for an operation mode, enter the hostname
and the system number of the application server. By using <relocci> to
fill in the hostname field, the instance is working under control of the
CCMS after a failover without any change.
If an instance is running on the standby node in normal operation (and is
stopped when switching over), the control console shows this instance to
be down (for example, you will get a red node on a graphical display)
after the switchover.
IS1190 Installation Step:
A SAP Internet Communication Manager (ICM) may run as part of any
Application Server. It is started as a separate multi-threaded process
and can be restarted independently from the Application Server. E.g.
usage of BW web reporting, Business Server Pages (BSP) rely on ICM to
work properly. In scenarios using external web communication, one or
more SAP Web Dispatcher often accompanies the ICMs. The SAP Web
Dispatcher can be layed out redundantly with hardware load balancing.
SAP also allows Serviceguard Extension for SAP on Linux packaging for
a single Web Dispatcher.
To find out if ICM is configured as part of an Application Server, check
for the following SAP profile parameter:
rdisp/start_icman=TRUE
ICM gets switched over with the Instance package. In order to make it
work, ICM has to be registered with the Message Server using a virtual
IP address.