`service cman start` is hanging at "Starting fencing..." after making changes to sysctl's kernel.shm* in RHEL 5

Solution Verified - Updated -


  • What is the reason cman service is hanging at "starting fencing..." after making changes in sysctl.conf as part of DB tuning ?
  • Cluster manager service start is hang at "Starting Fencing ..."
# service cman start          
    Starting cluster: 
    Loading modules... done
    Mounting configfs... done
    Starting ccsd... done
    Starting cman... done
    Starting daemons... done
    Starting fencing... 


  • Red Hat Enterprise Linux 5 with the High Availability Add On
  • Any of the following sysctl tunables modified lower than their defaults:
    • kernel.shmmax
    • kernel.shmmin
    • kernel.shmall

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