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

SAP Supply Chain Management
Planning the Volume Manager Setup
Chapter 4 187
LVM Option 2: Full Flexibility - No Constraints
If multiple MaxDB based database components are either planned or
already installed, care must be taken how the storage volumes are
configured.
For configuring storage in a liveCache environment the following
directories are affected:
/sapdb/programs: The central directory with all liveCache/MaxDB
executables. The directory is shared between all liveCache/MaxDB
Instances that reside on the same host. It is possible to share the
directory via NFS between hosts. It is also possible to install different
MaxDB versions (e.g.: version 7.3 and version 7.4) on the same host. In
any case only one single directory for the liveCache/MaxDB binaries can
be configured. This then implies if two different MaxDB versions will be
used on the same system the installed binaries in /sapdb/programs will
have to be from the newer version.
/sapdb/data/config: This directory can be shared between
liveCache/MaxDB instances: the directories and files below this path
have instance specific names <LCSID>: (e.g.
/sapdb/data/config/<LCSID>.*). According to SAP this path setting
is static.
/sapdb/data/wrk: The working directory of the main liveCache/MaxDB
processes is also a subdirectory of the IndepData path for non-HA setups.
If a liveCache 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. In HA scenarios, for liveCache
versions lower than 7.6, this directory should move with the package.
Therefore, SAP provided a way to redefine this path for each
liveCache/MaxDB individually. Serviceguard Extension for SAP on
Linux expects the work directory to be part of the lc package. The mount
point moves from /sapdb/data/wrk to /sapdb/data/<LCSID>/wrk.
This directory should not be mixed up with the directory
/sapdb/data/<LCSID>/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.