Managing Serviceguard Extension for SAP, December 2007

Step-by-Step Cluster Conversion
SGeSAP Configuration
Chapter 3164
The following list summarizes how the behavior of SGeSAP is affected by
changing the CLEANUP_POLICY parameter:
• lazy – no action, no cleanup of resources
• normal – removes unused resources belonging to the own system
• strict - uses HP-UX commands to free up all semaphores and shared
memory segments that belong to any SAP Instance of any SAP
system on the host if the Instance is to be started soon. It uses
HP-UX to free up all semaphores and shared memory segments that
belong to any database if the SAP database is to be started soon.
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 running
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 which is 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.