Managing Serviceguard Extension for SAP on Linux (IA64 Integrity and x86_64), February 2008

Planning a File System Layout for SAP in a Serviceguard/LX Cluster Environment
Putting it all Together
Chapter 2 59
Putting it all Together
Considering the above discussion the following file system layout was
chosen:
Why SAP Provides sapcpe
Technically the file system /usr/sap/<SID>/SYS/exe/run could be
configured as an NFS mounted file system. The advantage of having
configured this as a LOCAL mounted file system instead of NFS allows
the SAP binaries in this directory to still be available in the case of a
network failure. On the other side even with an LOCAL mount if there is
a NFS failure there is a high probability other SAP components in the
SAP system depending on the network will also have failed. To
circumvent the disadvantage of LOCAL mounted file systems (overhead
of cluster wide copy of file system contents to all cluster nodes) SAP is
providing “sapcpe” – a tool that automatically updates the contents of
/usr/sap/<SID>/SYS/exe/run.
In clustered SAP environments it is recommended to use local copies of
the SAP executables. Local executables limit the dependencies between
the SAP package and the database package of a two package installation
to a minimum. They allow SAP packages to shutdown even if HA NFS is
not available. To automatically keep the local executables of any instance
in sync with the latest installed patches, SAP developed the sapcpe
Table 2-4 SAP CI Instance
Path Type
/usr/sap/trans/ NFS
/usr/sap/tmp/ LOCAL
/usr/sap/<SID>/DVEBMGS00/ EXCLUSIVE to this ABAP CI INSTANCE
/usr/sap/<SID>/SYS/ LOCAL
/sapmnt/<SID>/ NFS
/home/<SID>adm LOCAL