Managing Serviceguard Extension for SAP on Integrity Linux, December 2005

Understanding Serviceguard Extension for SAP on Integrity Linux
Planning the LVM Layout for Clustered SAP Environments
Chapter 120
• <SID> the SAP System ID of the referred SAP component in
uppercase.
• <sid> the SAP System ID of the referred SAP component in
lowercase.
• <DBSID> a database System ID; usually identical to a <SID>.
• <INSTNR> SAP Instance Number of the referred SAP instance.
• <recocci> relocatable IP address of a CI package on a client subnet.
• <relocci_s> relocatable IP address of a CI package on a dedicated
server subnet.
SAP LVM Layout
The following section discusses how SAP specific volume groups should
be distributed across Serviceguard packages.
Volume groups can be either:
• Instance specific or
• System or Environment specific
Instance specific volume groups are required by only one SAP or
database instance. It makes sense to make them part of the package of
this instance. Packages of type DBCI and CI have SAP instance specific
volume group(s). DB and DBCI packages have database instance specific
volume groups.
System specific volume groups get accessed from all instances that
belong to a particular SAP System. Environment specific volume groups
get accessed from all instances that belong to all SAP Systems installed
in the whole SAP environment. System specific and environment specific
volume groups are often part of a database package of SGeSAP/LX IPF
package type DB or type DBCI and get secured via HA NFS mechanisms.
It is recommended to separate the environment specific volume groups to
a dedicated HA NFS package. This package will be referred to as SAPNFS
package. It should remain running all the time, since it is of central
importance for the whole setup. Since SAPNFS is just serving networked
filesystems, there is rarely a need to stop this package anyway. If
environment specific volume groups become part of a database package,
there will be a potential dependency between packages of different SAP
Systems. Stopping one SAP System by halting all related Serviceguard