Use the mod_whatkilledus module
When things go really bad, and Apache server crashes, The mod_whatkilledus module can be used to log detailed technical information about the crash together with the original client request which caused it. Additionally, if the mod_backtrace module is enabled, a backtrace showing the point of failure would be included, which is useful to annotate error logs with backtraces after certain conditions are met. For Unix systems, these modules will only function if the
--enable-exception-hook argument is enabled on the
httpd build. On the other hand, there are no specific requirements for Windows systems. Setup and configuration instructions for
mod_backtrace can be found from here.
Check third-party modules
It’s possible that third-party modules could be causing the issues that you are encountering with your Apache HTTP Server install. Therefore, you should disable all third party modules and check if the issue can still be reproduced. If disabling these modules solved the issue, you can then try to re-enable each module one by one in order to identify by elimination which of the modules was causing the issue.
The final part in the series on Troubleshooting Apache will deal with debugging tools and issues with script execution
Read the previous article in the series: Apache HTTP Server logs