Apache service failed to start, semaphore not released

1. Apache failure

Because Apache has been hot deployed with reload before, some mutex semaphores may not be released, resulting in unable to apply. Sometimes, Apache will fail to start/load, and some errors will be reported as follows — & gt;

[email protected] httpd]# tail error_log
[Mon Jun 28 16:34:28.797261 2021] [core:notice] [pid 31927] SELinux policy enabled; httpd running as context system_u:system_r:httpd_t:s0
[Mon Jun 28 16:34:28.799903 2021] [suexec:notice] [pid 31927] AH01232: suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Jun 28 16:34:28.816970 2021] [core:emerg] [pid 31927] (28)No space left on device: AH00023: Couldn't create the proxy mutex 
[Mon Jun 28 16:34:28.818127 2021] [proxy:crit] [pid 31927] (28)No space left on device: AH02478: failed to create proxy mutex
[Mon Jun 28 16:34:28.818141 2021] [:emerg] [pid 31927] AH00020: Configuration Failed, exiting
[Mon Jun 28 16:37:30.133663 2021] [core:notice] [pid 32151] SELinux policy enabled; httpd running as context system_u:system_r:httpd_t:s0
[Mon Jun 28 16:37:30.134915 2021] [suexec:notice] [pid 32151] AH01232: suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Jun 28 16:37:30.147614 2021] [core:emerg] [pid 32151] (28)No space left on device: AH00023: Couldn't create the proxy mutex 
[Mon Jun 28 16:37:30.147647 2021] [proxy:crit] [pid 32151] (28)No space left on device: AH02478: failed to create proxy mutex
[Mon Jun 28 16:37:30.147667 2021] [:emerg] [pid 32151] AH00020: Configuration Failed, exiting

2. Solutions

Then execute the following statement to release the synchronization semaphore

ipcs | grep apache | awk  '{print $2}'  >  signal.txt
for  i  in  `cat  signal.txt` ;  do  { ipcrm -s $i; } ;  done;

3. Restart Apache again


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