Managing Serviceguard Extension for SAP Version A.06.00 for Linux, December 2012

NOTE: SGeSAP packages and service monitors require SAP tools. Patching the SAP kernel
sometimes also patches SAP tools. Depending on what SAP changed, this might introduce additional
dependencies on shared libraries that weren't required before the patch. Depending on the shared
library path settings (LD_LIBRARY_PATH) of the root user, it may not be possible for SGeSAP to
execute the SAP tools after applying the patch. The introduced additional libraries are not found.
Creating local copies of the complete central executable directory prevents this issue.
The following sections details the different storage options.
Option 1: SGeSAP NFS cluster
With this storage setup, SGeSAP makes extensive use of exclusive volume group activation.
Concurrent shared access is provided via NFS services. Automounter and cross-mounting concepts
are used in order to allow each node of the cluster to switch roles between serving and using NFS
shares. It is possible to access the NFS file systems from servers outside of the cluster that is an
intrinsic part of many SAP configurations.
Common directories that are kept local
The following common directories and their files are kept local on each node of the cluster:
Table 4 List of common directories
DescriptionDirectory
Home directory of the SAP system administrator with node
specific startup log files
/home/<sid>adm
Home directory of the SAP diagnostic agent administrator/home/<dasid>adm
Directory holding local copies of SAP instance executables,
libraries, and tools (optional for kernel 7.x and higher).
/usr/sap/<sid>/SYS/exe/run>
Directory where the SAP operating system collector keeps
monitoring data of the local operating system
/usr/sap/tmp
Directory where SAP control services for the local host are kept
(kernel 7.x and higher).
/usr/sap/hostctrl
CCMS agent work directory (6.40 and 7.00 only)/usr/sap/ccms
List of startup service started by sapinit (boot)/usr/sap/sapservices
Depending on database vendor and version, it might be required to keep local database client
software. Details can be found in the database sections below.
All files belonging to the cluster software and runtime environment are kept local.
Part of the content of the local group of directories must be synchronized manually between all the
nodes of the cluster. Serviceguard provides a tool cmcp(1) that allows easy replication of a file
to all the cluster nodes.
SAP instance (startup) profile names contain either local hostnames or virtual hostnames. SGeSAP
A.06.00 prefes profiles with virtual hostname and uses those with local hostnames only for fallback
and backwards compatibility.
In clustered SAP environments prior to 7.x releases, local executables must be installed. Local
executables help to prevent several causes of 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. It is a good practice
to create local copies for all files in the central executable directory. This includes shared libraries
delivered by SAP.
SAP Instance Storage Considerations 31