Followed the instructions listed here: http://nagios.sourceforge.net/docs/3_0/quickstart-opensuse.html
Here are the changes I made to get Nagios to play with Apache2 installed via source.
#1 Make sure to add the web server user to the nagcmd group. Mine wasn’t wwwrun
#2 I created a symbolic link from the directory nagios was extracted to as follows: ln -s nagios-X.X.X nagios
#3 Once you run the ./configure –with-command-group=nagcmd the summary for my config was showing the Apache2 conf.d directory under /etc/apache2/conf.d since Apache was installed via source, it was located elsewhere on the system. I accepted the defaults and chose to make all anyway.
Then I started up again at make install, make install-init, make install-commandmode, make install-config
In addition you can run make install-webconf and this will but the Apache nagios.conf it the Apache conf.d directory, you will want to copy this to the location of your Apache extra files.
I actually had multiple virtual hosts on my server so I had to copy the nagios.conf text into a subsection of a virtual host and then reload Apache. service httpd reload
Configured Nagios according to the documentation and started it, added it into chkconfig –add