HP Serviceguard Extension for SAP (SGeSAP) manual Maxdb Storage Considerations

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. SAP allows you to redefine this path for each liveCache/MAXDB individually. SGeSAP 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.

NOTE: For liveCache starting with version 7.6 these limitations do not exist any more. The working directory is utilized by all instances (IndepData/wrk) and can be globally shared.

/var/spool/sql: This directory hosts local runtime data of all locally running liveCache/MAXDB Instances. Most of the data in this directory becomes 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 almost always very small (< 1MB).

Table 4-4 General File System Layout for liveCache (Option 3)

Storage Type	Package	Mount Point
shared	lc<LCSID>	/sapdb/<LCSID>
shared	lc<LCSID>	/sapdb/<LCSID>WRK*
shared	lc<LCSID>	/sapdB/<LCSID>/datan
shared	lc<LCID>	/sapdb/<LCSID>/saplogn
shared	sapnfs	/export/sapdb/programs
autofs shared	sapnfs	/export/sapdb/data
autofs shared	sapnfs	/var/spool/sql/ini

* only valid for liveCache versions lower than 7.6.

Option 4: Hot Standby liveCache

Two liveCache instances are running in a hot standby liveCache cluster during normal operation. No instance failover takes place. This allows to keep instance-specific data local to each node. The cluster design follows the principle to share as little as possible.

The following directories are relevant:

Table 4-5 File System Layout for Hot Standby liveCache

Access Point	Package	Mount Point	Volume Manager
local	none	/sapdb/<LCSID>	any
local	none	/sapdb/programs	any
local	none	/sapdb/data	any
local	none	/var/spool/sql/ini	any
local; with XP BCVs	none	/sapdb/<LCSID>/datan	must be LVM-based
between the nodes
shared disk and CFS	SG-CFS-DG-<LCSID>logn	/sapdb/<LCSID>/logn	must be CVM-based
	SG-CFS-MP-<LCSID>logn

MAXDB Storage Considerations

SGeSAP supports current MAXDB, liveCache and older MAXDB releases. The considerations made below will apply similarly to MAXDB,liveCache and MAXDB clusters unless otherwise indicated.

MAXDB Storage Considerations 97