Hi obomheire, the Loopback interfaces are used for unnumbered Interfaces or Management reasons and some other reasons.The thaught is a little different too the Hosts Loopback Interfaces. Take also a look here https://learningnetwork.cisco.com/thread/...

Hello Jalali,try nagios it works on Linux and its free.http://www.nagios.org/ There are a lot of Plugins for Cisco Router and Switches.Greats Andreas