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;

root@lry 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