Where should set EXTSHM=ON on AIX 5.3?

Document ID : KB000051495
Last Modified Date : 14/02/2018
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Description:

Environment
AIX: 5.3
Webserver: Apache 2.0.47
Webagent: 6 QMR5 HF-29

Webagent was throwing shared memory allocation errors
[09/Jul/2009:09:43:41] [Error] [CA WebAgent IPC] [454890] [CSmSharedSegment:: _
smalloc] Error attaching to shared memory segment 9 - Too many open files (24)

and

[13/Jul/2009:16:23:12] [Error] [CA WebAgent IPC] [503834] [CSmSharedSegment::smalloc]
Error attaching to shared memory segment
8 - Too many open files (24)

Suggested to add EXTSHM=ON to the apache startup script that resolved the issue.

But, if EXTSHM=ON is set in /etc/sysconfig/httpd
then :

vi /etc/sysconfig/httpd
LD_PRELOAD=/opt/siteminder6/webagent/bin/libbtunicode.so:$LD_PRELOAD
LIBPATH=/opt/siteminder6/webagent/bin:$LIBPATH
PATH=/opt/siteminder6/webagent/bin:$PATH
NETE_WA_PATH=/opt/siteminder6/webagent/bin
NETE_WA_ROOT=/opt/siteminder6/webagent
LD_LIBRARY_PATH=/opt/siteminder6/webagent/bin:$LD_LIBRARY_PATH
EXTSHM=ON
export LD_PRELOAD
export LD_LIBRARY_PATH
export LIBPATH
export PATH
export NETE_WA_PATH
export NETE_WA_ROOT
export EXTSHM

Q. Where EXTSHM=ON should be set?

Solution:

EXTSHM is an environment variable and should be set in the environment prior to the web server starting.
How this is done is not relevant as long as it is there.
This is not something that the web agent is using but the OS process itself. For best practices on setting this env variable please use the IBM documentation for the platform.