I was having difficulty setting up passive service checks with Nagios. The problem was not enough documentation on the Internet in regard to getting the NSCA addon up and running. I figured if I was having difficulty then others were as well. So I created a PDF for reference.
The PDF contains:

• Setting up NSCA on both the master Nagios server and client host.
• Creating a container and crontab entry for the passive check on the client host.
• Setting up the service configuration file on the master host.
• Perl container script to extract the state from a command and only send it to the master Nagios server when the state changes.

The document is covered under the GNU license, so please read the license agreement.
As always, please try to patronize my sponsors so I can keep bringing this information to the Nagios community.
Enjoy,
Mike Kniaziewicz, MIS
Distributed_Monitoring