Managing Serviceguard Extension for SAP Version B.05.10, September 2010

NOTE: Do not use the strict policy unless it is critical that you do. Be aware that the strict option
can crash running instances of different SAP systems on the backup host. Use this value only if
you have a productive system that is much more important than any other SAP system you have.
In this case, a switchover of the productive system is more robust, but additional SAP systems
will crash.
You can also use strict policy, if your SAP system is the only one unning at the site and you are
low on memory. Strict policy frees up more of its own shared memory segments than the normal
policy does.
For the cleanup of resources cleanipc is used—an SAP tool to free up the IPC resources of
specific SAP Instances. It is used to free up resources of an Instance that is to be started soon on
HP-UX. This prevents shared memory issues caused by the remains of a prior crash of the Instance.
Accordingly, an obsolete ORACLE SGA is also removed if a database crash occurred.
Optional Parameters and Customizable Functions
In /etc/cmcluster/<SID> there is a file called customer.functions that provides a couple
of predefined function hooks. They allow the specification of individual startup or runtime steps
at certain phases of the package script execution. Therefore, it is not necessary and also not
allowed to change the sap.functions.
In the following, there is a summary of the function hooks in chronological order:
Table 3-7 Optional Parameters and Customizable Functions List
Description:Command:
Additional startup steps on database host after all low-level resources are made
available after the system has been cleaned up for db start before start of
database instance.
start_addons_predb
Additional startup steps on database host after start of the database instance.
start_addons_postdb
Additional startup steps on Central Instance host after start of the database
instance.
start_addons_preci
Additional startup steps on Central Instance host after start of the Central
Instance before start of any Application Server Instance.
start_addons_postci
Additional startup steps that are performed on the Central Instance host after
startup of all Application Server Instances.
start_addons_postciapp
Equally, there are hooks for the stop procedure of packages:
Usually this function contains actions that relate to what has been added to
start_addons_postciapp.
stop_addons_preciapp
Relates to start_addons_postci.stop_addons_preci
Relates to start_addons_preci.stop_addons_postci
Relates to start_addons_postdb.stop_addons_predb
Relates to start_addons_predb.stop_addons_postdb
The customer.functions template that is delivered with SGeSAP provides several examples
within the hook functions. They can be activated via additional parameters as described in the
following.
Stubs for JAVA based components work in a similar fashions.
Optional Step: OS740
SAPROUTER is an example for an additional program that always starts on the Central Instance
host.
90 Step-by-Step Cluster Conversion