Error : Creating semaphore - No space left on device (28) on Web Agent

Products

• CA Single Sign On Secure Proxy Server (SiteMinder)
• CA Single Sign On SOA Security Manager (SiteMinder)
• CA Single Sign-On
• SITEMINDER
• CA Single Sign On Agents (SiteMinder)

Issue/Introduction

 

When running more than 19 Apache Instances on the same machine with
Web Agent.

Starting them one by one, the 9th Apache instance fails to start and
reports error :

  [06/Jun/2016:08:39:41] [Info] [CA WebAgent IPC] [14227]
  [CSmSem::getSem] Attempted to attach to non-existent semaphore with key 0xc81d247f

  [06/Jun/2016:08:39:41] [Error] [CA WebAgent IPC] [14227]
  [CSmSem::getSem] Error creating semaphore using key 0xc81d247f - No space left on device (28)

  [06/Jun/2016:08:39:41] [Error]
  SiteMinder Agent Failed to Start the LLAWP process. Failed to initialize the server start mutex.

 

Environment

 

Web Agent 12SP3CR12 on Apache 2.2 on Redhat 6 64 bit

 

Cause

 

The issue happens because not enough semaphore are available on the
OS. Check them SMMNS value for the maximum semaphore on RedHat. In the
following output, 32000 is the SMMNS.

  cat /proc/sys/kernel/sem
  250 32000 32 128

 

Resolution

 

To solve the issue, increase the semaphore available on the system and
adjust the SEMMSL, SEMOPM, and SEMMNI value according to the one you
set for the SMMNS one (1).

 

Additional Information

 

(1)

    Semaphore limits and many Apache instances on Linux
    https://www.endpointdev.com/blog/2011/12/semaphore-limits-and-many-apache/