User's Guide

A hot standby initialization during startup might require hardware-based copy mechanisms of the underlying
storage array. Currently HP StorageWorks XP arrays with BCV volumes are supported. The following
parameter needs to be set:
LC_COPY_MECHANISM=BUSINESSCOPY
Optional hot standby Installation Step: LC197
A hot standby initialization procedure can perform a plausibility check of its storage configuration.
A hot standby initialization procedure can perform a plausibility check of its storage configuration. Presaved
world-wide IDs of LUNs are compared with current world-wide IDs to prevent that outdated configuration
information is used for cloning. This adds to the robustness of the initialization process, but for large
implementations it significantly slows down the standby startup. By setting:
AVOID_WWID_CHECK=1
in sap.config the check can be turned off.
Optional hot standby Installation Step: LC198
The hot standby liveCache instance does not detect a regular liveCache master shutdown.
It will not reconnect to the restarted liveCache master. The sap.config parameter
LC_STANDBY_RESTART=1
will (re)start a remote hot standby system after the master liveCache instance package is started.
Optional hot standby Installation Step: LC200
You can optionally handle SAP ABAP Application Servers with a liveCache package.
Refer to Chapter 3 - SGeSAP Configuration to get more information on the usage of the parameters ASSID,
ASHOST, ASNAME, ASNR, ASTREAT and ASPLATFORM
liveCache Installation Step: LC205
Distribute the content of /etc/cmcluster/<LCSID> to all cluster nodes on which the liveCache should
be able to run.
liveCache Installation Step: LC210
Log in on the primary node that has the shared logical volumes mounted.
Create a symbolic link that acts as a hook that informs SAP software where to find the liveCache monitoring
software to allow the prescribed interaction with it. Optionally, you can change the ownership of the link to
sdb:sdba.
ln -s /etc/cmcluster/<LCSID>/saplc.mon \ /sapdb/<LCSID>/db/sap/lccluster
liveCache Installation Step: LC215
For the following steps the SAPGUI is required. Logon to the APO central instance as user SAP*.
Start transaction /nlc10 and enter LCA for the logical connection.
/nlc10 -> Logical connection -> LCA -> liveCache -> Create/Change/Delete
Connection
Change liveCache server name to the virtual IP name for the liveCache and save it.
Change the liveCache instance name to <LCSID>. Redo the above steps for LDA.
Livecache Service Monitoring
SAP recommends the use of service monitoring in order to test the runtime availability of liveCache processes.
The monitor, provided with SGeSAP, periodically checks the availability and responsiveness of the liveCache
system. The sanity of the monitor will be ensured by standard Serviceguard functionality.
The liveCache monitoring program is shipped with SGeSAP in the saplc.mon file. The monitor runs as a
service attached to the lc<LCSID> Serviceguard package.
If the monitor recognizes the liveCache to be unavailable, it will promote the hot standby system to become
the new master. If no hot standby is available, the monitor will try to restart liveCache on the node it is
currently running. If this does not succeed, the runtime operating system resources of liveCache are cleaned
up and another local restart attempt is made. If this still does not bring liveCache back to work and a failover
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