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

installed on the same host. The files in /sapdb/programs have to be of the newest version that any
MaxDB on the cluster nodes uses. Files in /sapdb/programs are downwards compatible.
• /sapdb/data/config: This directory is also shared between instances, though you can find lots of
files that are Instance specific in here, e.g. /sapdb/data/config/<SID>.* According to SAP this
path setting is static.
• /sapdb/data/wrk: The working directory for MaxDB. If a MaxDB restarts after a crash, it copies
important files from this directory to a backup location. This information is then used to determine the
reason of the crash. For MaxDB versions lower than version 7.5, this directory should move with the
package. Therefore, SAP provided a way to redefine this path for each MaxDB individually. Serviceguard
Extension for SAP on Linux expects the work directory to be part of the database package. The mount
point moves from /sapdb/data/wrk to /sapdb/data/<SID>/wrk for the clustered setup. This
directory should not be mixed up with the directory /sapdb/data/<DBSID>/db/wrk that might also
exist. Core files of the kernel processes are written into the working directory. These core files have file
sizes of several Gigabytes. Sufficient free space needs to be configured for the shared logical volume
to allow core dumps.
NOTE: For MaxDB starting with version 7.6 these limitations do not exist anymore. The working directory
is used by all instances and can be globally shared.
▲ /var/spool/sql: This directory hosts local runtime data of all locally running MaxDB instances.
Most of the data in this directory would become meaningless in the context of a different host after
failover. The only critical portion that still has to be accessible after failover is the initialization data in
/var/spool/sql/ini. This directory is usually very small (< 1Megabyte). With MaxDB and liveCache
7.5 the only local files are contained in /var/spool/sql/ini, other paths are just links to local
runtime data in IndepData path:
dbspeed -> /sapdb/data/dbspeed
diag -> /sapdb/data/diag
fifo -> /sapdb/data/fifo
ipc -> /sapdb/data/ipc
pid -> /sapdb/data/pid
pipe -> /sapdb/data/pipe
ppid -> /sapdb/data/ppid
The links need to exist on every possible failover node where the MaxDB or liveCache instance is able to
run:
▲ /etc/opt/sdb: Only exists when using MAXDB or liveCache 7.5 or higher. Needs to be local on
each node.
NOTE: In high availability scenarios, valid for MaxDB versions up to 7.6, the runtime directory
/sapdb/data/wrk is configured to be located at /sapdb/<DBSID>/wrk to support consolidated failover
environments with several MaxDB instances. The local directory /sapdb/data/wrk though is still referred
to by the MaxDB vserver processes (vserver, niserver), which means vserver core dump and log files
will be located there.
Table 2-9 MaxDB mount points and SGeSAP/LX packages:
SGeSAP/LX PackageAccess TypeMount Point
noneLOCAL/etc/opt/sdb
db<SID>EXCLUSIVE/sapdb/<SID>
Conclusion: Mount Points, Access Types and SGeSAP/LX Package 43