Log POST data in Apache

By | 2013/02/08

Apache can log all POST data for troubleshooting purposes. I’ll show you how to set this up!


First you will need to enabled mod_dumpio.

On Ubuntu / Debian enable the module:

$ sudo a2enmod dump_io

Then add the following and restart apache:

$ sudo nano /etc/apache2/apache2.conf
LogLevel debug
DumpIOInput On
DumpIOOutput On
DumpIOLogLevel debug # optional - Apache 2.2.4 or later only

Red Hat / CentOS:

$ sudo nano /etc/httpd/conf/httpd.conf

Add the following:

LoadModule dumpio_module modules/mod_dumpio.so

LogLevel debug
DumpIOInput On
DumpIOOutput On
DumpIOLogLevel debug # optional - Apache 2.2.4 or later only

The POST data is then logged to the error_log for Apache. /var/log/httpd/error_log (Red Hat) or /var/log/apache2/error.log (Debian).

Be careful as logs will grow to be very huge in size! Only use this to debug special case scenarios.