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

NOTE: <LCSID> is the system id of the particular implementation a liveCache system. <LCSID> denotes
the three-letter database name of the liveCache instance in uppercase.<lcsid>is the same name in lowercase.
The term MaxDB based components and liveCache, MaxDB and SAPDB: SABDB is the original name of a
database from SAP. The name SAPB was recently replaced by the name MaxDB. LiveCache is a memory
based variant of the MaxDB database.
There are different configuration options for the file systems caused by a tradeoff between simplicity and
flexibility. The options are described below ordered by increasing complexity. The cluster layout constraints
that need to be fulfilled to allow the simplifications of a given option are stated within a bullet list.
LVM Option 1: Simple Clusters with Separate Packages
Cluster Layout Constraints:
• The liveCache package does not share a failover node with the APO Central Instance package.
• There is no MAXDB or additional liveCache running on cluster nodes.
• There is no intention to install additional APO Application Servers within the cluster.
Table 4-1 File System Layout for liveCache Package running separate from APO (Option 1)
Device NumberLogical VolumeVolume groupMount PointPackageStorage Type
/sapdblc<LCSID>Shared
Exclusive
/sapdb/
<LCSID>/ datan
lc<LCSID>Shared
Exclusive
/sapdb
/<LCSID>/ logn
lc<LCSID>Shared
Exclusive
/var/spool/sqllc<LCSID>Shared
Exclusive
/sapdb
/programs
lc<LCSID>1Shared
Exclusive
/etc/opt/sdbLocal
1 This denotes the package for the database of the APO Central Instance. The logical volume should be
added to the logical volumes that already belong to this package.
In the above layout all relevant files get shared via standard procedures. The setup causes no additional
administration overhead for synchronizing local files. SAP default paths are used.
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
108 SAP Supply Chain Management