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

• /home/<sid>adm — the home directory of the SAP system administrator with node specific
startup log files.
• /usr/sap/<SID>/SYS/exe/run — the directory that holds a local copy of all SAP instance
executables, libraries, and tools (optional for kernel 7.x and higher).
• /usr/sap/tmp — the directory where the SAP operating system collector keeps monitoring
data of the local operating system.
• /usr/sap/hostctrl — the directory where SAP control services for the local host are
kept (kernel 7.x and higher).
• /etc/cmcluster — the directory where Serviceguard keeps its legacy configuration files
and the node specific package runtime directories.
• Local database client software needs to be stored locally on each node. Details can be found
in the database sections below.
Part of the content of the local group of directories must be synchronized manually between all
nodes of the cluster.
SAP instance (startup) profile names contain either local hostnames or virtual hostnames. SGeSAP
will always prefer profiles that use local hostnames to allow individual startup profiles for each
host, which might be useful if the failover hardware differs in size.
In clustered SAP environments prior to 7.x releases, install local executables. Local executables
help to prevent several causes for package startup or package shutdown hangs due to the
unavailability of the centralized executable directory. Availability of executables delivered with
packaged SAP components is mandatory for proper package operation. Experience has shown
that it is a good practice to create local copies for all files in the central executable directory. This
includes shared libraries delivered by SAP.
To automatically synchronize local copies of the executables, SAP components deliver the sapcpe
mechanism. With every startup of the instance, sapcpe matches new executables stored centrally
with those stored locally.
Directories that Reside on Shared Disks
Volume groups on a SAN shard storage get configured as part of the SGeSAP package.
Instance-specific volume groups are required by only one SAP instance or one database instance.
They usually get included with exactly the package that is set up for this instance. In this
configuration option, the instance-specific volume groups are included in the package.
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 any
SAP System installed in the whole SAP scenario. System and environment-specific volume groups
should be set up using HA NFS to provide access capabilities to SAP instances on nodes outside
of the cluster. The cross-mounting concept of option 1 is not required.
A valuable naming convention for most of these shared volume groups is vg<INSTNAME><SID>
or vg<INSTNAME><SID><INR>. Table 2-4 provide an overview of SAP shared storage for this
special setup and maps them to the component and package type for which they occur.
Table 2-4 File systems for the SGeSAP package in NFS Idle Standby Clusters
Device minor
number
VG NameRemarksAccess PointMount Point
requiredshared disk and
HA NFS
/sapmnt/<SID>
shared disk
/usr/sap/<SID>
optionalshared disk and
HA NFS
/usr/sap/trans
SAP Instance Storage Considerations 27