QuestionApache service goes down frequently on a Plesk for Linux Server: AH00484: server reached MaxRequestWorkers setting
Symptoms
- Apache constantly goes down with the error below:
server reached MaxRequestWorkers setting, consider raising the MaxRequestWorkers setting
- At the same time the MaxRequestWorkers value was increased but this does not solve the problem.
- There is high number of CLOSE_WAIT Apache connections on the server as on the following example:
netstat -tanp | grep httpd | awk '{print $6}' | sort | uniq -c | sort -n
..................
1700 CLOSE_WAIT- In an attempt to strace any of the CLOSE_WAIT connection processes only one domain, example.com is shown.
- Websites can be inaccessible with the error below in domain log file:
(70007)The timeout specified has expired
Cause
Issue with a website code causing high CLOSE_WAIT connections.
Resolution
- Log into Plesk.
- Suspend the domain example.com.
- Restart Apache and PHP handler that is used for example.com domain via Tools & Settings > Services Management.
Then and before enabling the domain again it is required to review the website code with its Developer or in case example.com is a WordPress instance, try to disable the plugins one by one until the culprit of this behavior is found.