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

Planning a File System Layout for SAP in a Serviceguard/LX Cluster Environment
About SAP Components
Chapter 244
AREP ABAP Replicated Enqueue Server. In a high-availability
environment the Enqueue Server component consists of
the standalone Enqueue Server and an enqueue
replication server. The Replicated Enqueue Server (AREP)
runs on another host and contains a replica of the lock
table (replication table). If the standalone Enqueue Server
fails, the Enqueue Server must be restarted on the host on
which the replication server is running, since this host
contains the replication table in a shared memory
segment. The restarted Enqueue Server needs this shared
memory segment to generate the new lock table.
Afterwards this shared memory segment is deleted.
Note: The modern SAP terminology for both REP and
AREP is Enqueue Replication Service (ERS).
REP JAVA Replicated Enqueue Server. Provides same
functionality as the ABAP Replicated Enqueue Server but
for the replication of the JAVA Enqueue Server.
liveCache A liveCache instance. SAP liveCache technology is an
enhancement of the MaxDB database system and was
developed to manage logistical solutions such as SAP
SCM/APO (Supply Chain Management / Advanced
Planning Optimizer). In contrast to MaxDB and for
performance reasons the database system is located in the
main memory instead of being file system based.
Table 2-3 SAP Component Terminology (Continued)
Term Definition