Managing Serviceguard Extension for SAP on Linux (IA64 Integrity and x86_64), April 2009

Using the data from the SHARED NFS sections from above, the following lines are added to the automounter
map file /etc/auto.import.
<SID> -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/sapmnt/<SID>
trans -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/usr/sap/trans
ini -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/var/spool/sql/ini/
programs -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/sapdb/programs
data -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/sapdb/data
stage -fstype=nfs,rw,udp,nosymlink nfsreloc:/export/oracle/stage
Lastly, create symbolic links that point from the original SAP and original database directory names to NFS
place holders in /import.
ln -sf /import/<SID> /sapmnt/<SID>
ln -sf /import/trans /usr/sap/trans
ln -sf /import/ini /var/spool/sql/ini
ln -sf /import/programs /sapdb/programs
ln -sf /import/data /sapdb/data
ln -sf /import/oracle/stage /oracle/stage
NOTE: The 2.6 Linux kernel use lvm2with the device-mapper and virtual devices. In a failover situation it
can happen that the device minor number changes when a volume group fails over to another node resulting
in 'stale NFS handle' errors. One solution to avoid this issue is to create logical volumes with persistent minor
numbers. See the README file in /opt/cmcluster/nfstoolkit or
/usr/local/cmcluster/conf/nfstoolkit for a detailed description.
Overview Serviceguard packages
A package groups application services together. A Serviceguard package consists of the following:
1. Package name
2. Virtual IP address /relocateable address
3. Application processes that run one cluster node and "belong" to that package
4. Storage that "belongs" to the application that is started with this Serviceguard package.
The typical high availability package is a failover package. It usually is configured to run on several nodes
in the cluster, and runs on one at a time. If a service, node, network, or other package resource fails on the
node where it is running, Serviceguard can automatically transfer control of the package to another cluster
node, allowing services to remain available with minimal interruption.
The following describes how these components are used to implement a SGeSAP/LX package. The SGeSAP/LX
package name is derived from the SAP component type and / or functionality.
Table 2-6 Mapping of SAP components to Serviceguard Extension for SAP on Linux package types
DescriptionComponent
Database Instance for ABAP and JAVA components (db)DB
ABAP Central Instance (ci)ABAP CI
JAVA Central instance
Note: not recommended by SAP for switchover.
JAVA CI
ABAP SAP Central Services (ci)ASCS
JAVA SAP Central Services (jci)SCS
Dialog Instance (d)DI
ABAP Replicated Enqueue Server (arep)AREP
JAVA Replicated Enqueue Server (rep)REP
40 Planning a File System Layout for SAP in a Serviceguard/LX Cluster Environment