Layer7 Access Management

Tech Tip : CA Single Sign-On : When doing Apache graceful restart, Web Agent reports error "PID Cache error"

  • 1.  Tech Tip : CA Single Sign-On : When doing Apache graceful restart, Web Agent reports error "PID Cache error"

    Posted 01-10-2018 03:16 AM

    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

     

    KB : TEC1866425