7021224: Apache fails to start on RHEL 7.3 after upgrade to NAM 4.4

Increase the number of semaphore arrays on the RHEL 7.3 OS kernel settings. The following steps indicates how to increase number of semaphore arrays

1) Open /etc/sysctl.conf and add the following line,

kernel.sem = 250 256000 32 1024

—— Semaphore Limits ——–
max number of arrays = 1024
max semaphores per array = 250
max semaphores system wide = 256000
max ops per semop call = 32

Based on the requirement [no. of proxy services * 2] has to be chosen to be the minimum number of “max number of arrays” value. Accordingly following condn should also be maintained

Max semaphores system wide = max no. of arrays * max semaphores per array

2) Run sysctl –p in the command line for the changes to reflect.

3) Now start apache. ( If not modify the parameter limits based on the no. of balancers)


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