Why can't I get Apache2 mod_dumpio working und

Question

I did the following to try to set mod_dumpio up properly:

1. Used a2enmod to enable mod_dumpio
2. Changed LogLevel to "debug" in apache2.config
3. Added "DumpIOInput On", "DumpIOOutput On" and "DumpIOLogLevel debug" to apache2.config
4. Issued "/etc/init.d/apache2 restart" to restart Apache
5. Issued "apache2ctl -t -D DUMP_MODULES" to make sure mod_dumpio was loaded

I'm watching /var/log/apache2/error.log, but not seeing much there, and certainly not a dump of all input and output.

Can anyone help?

Answer 1

Nobody talks about Windows (easyphp, xampp, etc) but the configuration is slightly different:

1. Edit "httpd.conf" apache configuration file :

   • Uncomment "LoadModule dumpio_module modules/mod_dumpio.so"

   • Add section:

     <IfModule dumpio_module>
       DumpIOInput On
       DumpIOOutput On
       #DumpIOLogLevel warn #NOT THIS LINE, DEPRECATED in apache 2.4 !
     </IfModule>
     

   • Change "LogLevel warn" to "LogLevel warn dumpio:trace7"

   • stop/start apache server

Answer 2

NM...got it!

The problem was apparently that just one of my VirtualHosts (as defined in /etc/apache2/sites-enabled) had a LogLevel declared that was something other than debug, thus interfering with the overall behavior of mod_dumpio for reasons that escape me :)

I hope someone else finds this helpful.

Answer 3

Typically the debug level is set to warn in your sites-enabled/default*, so the following code might help (e.g. as /etc/apache2/conf.d/dumpio.conf):

<IfModule dumpio_module>
  DumpIOInput On
  DumpIOOutput On
  DumpIOLogLevel warn
</IfModule>

Or to change the log level in your sites-enabled/default from LogLevel warn to LogLevel debug.

Answer 4

Mirroring @bland328 I had the same problem, my sub-conf file had "LogLevel debug" and this over-rode the global "LogLevel dumpio:trace7" that seems to be required for Apache 2.4.7. Note that much of the online help is in reference to earlier Apaches and 2.4 has some different syntax.

For reference using an out-of-the-box install on Ubuntu 13.04 I've got a vhosts conf and this is where I had to add the 3 DumpIO lines:

#conf-available/other-vhosts-access-log.conf 
# Define an access log for VirtualHosts that don't define their own logfile
CustomLog ${APACHE_LOG_DIR}/other_vhosts_access.log vhost_combined

LogLevel dumpio:trace7
DumpIOInput On
DumpIOOutput On

After this a sudo service apache2 restart and a curl with --data caused a lot of debug lines to appear in \var\log\apache2\error.log including the POST body, looking like:

[Thu Jul 03 14:39:58.878429 2014] [dumpio:trace7] [pid 12890] mod_dumpio.c(103): [client 10.84.17.174:51824] mod_dumpio:  dumpio_in (data-HEAP): {"bob":42}