Which network monitoring software to go for?

Hi,
We need to monitor our server, for this i need a constant ping software & also to monitor every server disk usage etc. What would you say about Orion Network Performance Monitor? Any other recommendations?

nagios :thumbup1:

Yes it takes time for setup. but if you are well known with linux then no problem it will do alot of things for you & that too for free.

I also needed some kinds of network monitoring software before. But now I use this NetVizor; it's working fine. You can take a look at it.