If you are not able to restart apache successfully on your linux server , Please check the error with apache error logs

tail -f /usr/local/apache/log/error_log

if you are getting

pid file /usr/local/apache/logs/httpd.pid overwritten —
Unclean shutdown of previous Apache run?
semget: No space left on device

you can get it resolved with following steps:

The error specifies that there is no more space left in Semaphore Arrays for Apache. You can check the semaphore are with

#ipcs -s

The result will be as

—— Semaphore Arrays ——–
key semid owner perms nsems
0×00000000 9601024 nobody 600 1
0×00000000 9633793 nobody 600 1

So you need to remove nobody

#for i in `ipcs -s | awk ‘{print $2}’`; do ipcrm -s $i;done

then restart apache services

#service httpd restart