Managing Serviceguard Extension for SAP Version B.05.10, December 2012

The sap_virtual_hostname parameter corresponds to the virtual hostname that got specified
during SAP installation. The SAP virtual hostname is a string value. It is not possible to specify the
corresponding IPv4 or IPv6 address. If the string is empty, the DNS resolution of the first specified
package ip_address parameter will be substituted. In this case, the script only works properly
if reliable address resolution is available. Domain name extensions are not part of the virtual
hostname.
SAP Enqueue Replication Service instances (ERS) have the purpose to keep track of the runtime
status of a SAP Central Service instance. They allow for a more seamless failover experience. For
each SAP Replication Service that is part of the package, the corresponding, replicated Central
Service instance needs to be specified in the sap_replicated_instance parameter.
It is possible to put several SAP instances into one package by specifying sap_instance and
the corresponding sap_virtual_hostname and sap_replicated_instance parameters
more than once. SAP infrastructure software that does not come as part of an instance can not be
specified here.
Example:
sap_instance D03
sap_instance J33
sap_instance DVEBMGS00
sap_virtual_hostname reloc2
sap_instance ERS02
sap_virtual_hostname reloc3
sap_replicated_instance SCS01
Optional Step: OS441
If the software health of a SAP System Central Service instance ([A]SCS) should be monitored in
order to detect SAP software malfunctions with the cluster, the package configuration file needs to
configure service monitoring for the SAP message server.
Monitoring Routines periodically check the availability and responsiveness of the SAP Message
Server.
The message server should generally be configured to restart locally by specifying restart in the
SAP (start) profile. If Serviceguard recognizes the SAP Message Server to be unavailable for a
longer period of time, it assumes that the restart doesn’t work or is accidentally not configured.
Serviceguard will switch the package and try to restart on different hardware, usually the active
enqueue replication server. SGeSAP service monitors will be paused within 30 seconds (based on
default value of timer in monitor) if a debug file gets created for the package. For details see
chapter 6 –”SGeSAP Cluster Administration.” The debug file can be used to allow manual SAP
instance shutdowns and startups. Make sure that all packaged SAP components are running when
removing the debug file. Otherwise a failover will occur.
NOTE: The message server monitor works without command line parameters in the service
command string service_cmd. It will configure itself automatically during startup and monitors
all message servers that are clustered within the package.
Example entries for the package configuration file:
service_name scsC11ms
service_cmd “/opt/cmcluster/sap/SID/sapms.mon”
service_restart 2
service_fail_fast_enabled no
service_halt_timeout 300
Optional Step: OS446
If the enqueue service of the SAP System Central Services should also be handled, the automated
Replicated Enqueue handling including follow-and-push failover semantics needs to be activated
for a [A]SCS/ERS package pair:
84 Step-by-Step Cluster Conversion