Apache > HTTP Server > Documentation > Version 2.4 > Modules

Apache MPM Common Directives

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Description:A collection of directives that are implemented by more than one multi-processing module (MPM)



CoreDumpDirectory Directive

Description:Directory where Apache HTTP Server attempts to switch before dumping core
Syntax:CoreDumpDirectory directory
Default:See usage for the default setting
Context:server config
Module:event, worker, prefork

This controls the directory to which Apache httpd attempts to switch before dumping core. If your operating system is configured to create core files in the working directory of the crashing process, CoreDumpDirectory is necessary to change working directory from the default ServerRoot directory, which should not be writable by the user the server runs as.

If you want a core dump for debugging, you can use this directive to place it in a different location. This directive has no effect if your operating system is not configured to write core files to the working directory of the crashing processes.

Core Dumps on Linux

If Apache httpd starts as root and switches to another user, the Linux kernel disables core dumps even if the directory is writable for the process. Apache httpd (2.0.46 and later) reenables core dumps on Linux 2.4 and beyond, but only if you explicitly configure a CoreDumpDirectory.

Core Dumps on BSD

To enable core-dumping of suid-executables on BSD-systems (such as FreeBSD), set kern.sugid_coredump to 1.

Specific signals

CoreDumpDirectory processing only occurs for a select set of fatal signals: SIGFPE, SIGILL, SIGABORT, SIGSEGV, and SIGBUS.

On some operating systems, SIGQUIT also results in a core dump but does not go through CoreDumpDirectory or EnableExceptionHook processing, so the core location is dictated entirely by the operating system.