Nagios Support Forum

how to create services to monitor firewalls?
does it need a plugin to install?

This all depends on the plugin you will be using, please use the exchange to find one suitable, then follow the second link below for help formatting a command, host.cfg and service.cfg to use with that plugin:

http://exchange.nagios.org/

http://nagios.sourceforge.net/docs/nagi ... n/toc.html

http://nagios.sourceforge.net/docs/3_0/ ... .html#host

http://nagios.sourceforge.net/docs/3_0/ ... ml#service