The monitoring daemon runs intermittent checks on hosts and services you specify using external "plugins" which return status information to Nagios. When problems are encountered, the daemon can send notifications out to administrative contacts in a variety of different ways (email, instant message, SMS, etc.). Current status information, reports, and historical logs can all be accessed via a web browser.CGI programs are included to allow you to view the current status, history, etc via a web interface if you so desire.Here are some key features of "Nagios":

Ссылка: http://kent.dl.../sourceforge/nagios/nagios-3.1.2.tar.gz