When doing Apache graceful restart, Web Agent reports error "PID Cache error"

Document ID : KB000007127
Last Modified Date : 14/02/2018
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Issue:

We are running Web Agent on Apache, and when we restart Apache server with the 
command : 

/local/opt/bin/scripts/service reload myinstance 

then the Web Agent reports errors : 

error.log : 

May 23 14:19:36 myhost [23/May/2017:14:19:36] [Info] [CA WebAgent IPC] 
[31025] [CSmSem::getSem] Attempted to attach to non-existent semaphore with key 0x6beecd05 
May 23 14:19:36 myhost [23/May/2017:14:19:36] [Info] [CA WebAgent IPC] 
[31025] [CSmSem::getSem] Attempted to attach to non-existent semaphore with key 0x6beecd05 
May 23 14:19:36 myhost [23/May/2017:14:19:36] [Info] [CA WebAgent IPC] 
[31025] [CSmSem::getSem] Created semaphore 30081042 using key 0x6beecd05 
May 23 14:19:36 myhost [23/May/2017:14:19:36] [Error] [CA WebAgent IPC] 
[31025] [CSmSharedSegment::smalloc] Error allocating shared memory segment using key 0x6ceecd05 - 
File exists (17) 
May 23 14:19:36 myhost [23/May/2017:14:19:36] [Info] [CA WebAgent IPC] 
[31025] [CSmSem::SemRm] Removed semaphore 30081042 
May 23 14:19:36 myhost [23/May/2017:14:19:36] [Error] SiteMinder Agent 
May 23 14:19:36 myhost PID Cache error. 
May 23 14:19:36 myhost Failed to initialize PID Cache 
May 23 14:19:40 myhost nm: '/local/opt/bin/httpd': No such file 
May 23 14:19:40 myhost [Tue May 23 14:19:40 2017] [warn] Siteminder Web Agent: 
restart not supported. 

Cause:

When you ran nm -A against /usr/sbin/httpd and /usr/sbin/httpd.worker on the RedHat Apache and you get the message :

 

"no symols".

 

[root@localhost /opt]# nm -A /usr/sbin/httpd

nm: /usr/sbin/httpd: no symbols

 

For the Agent to be able to support graceful restart, symbols should be available. That's the only way the Agent can handle the restart.

 

Resolution:

Compile your own Apache or get an Apache version which binaries will show symbols.

The command 

nm -A against /usr/sbin/httpd 

should return symbols