nagios 4.4.6 Host, service, and network monitoring program
Nagios is a host, service, and network monitoring program written in C. CGI programs are included to allow you to view the current status, history, etc. via a Web interface. Features include:
Monitoring of network services (via SMTP, POP3, HTTP, PING, etc).
Monitoring of host resources (processor load, disk usage, etc.).
A plugin interface to allow for user-developed service monitoring methods.
Ability to define network host hierarchy using "parent" hosts, allowing detection of and distinction between hosts that are down and those that are unreachable.
Notifications when problems occur and get resolved (via email, pager, or user-defined method).
Ability to define event handlers for proactive problem resolution.
Automatic log file rotation/archiving.
Optional web interface for viewing current network status, notification and problem history, log file, etc.