[CentOS] Re: [OT] What is the best network monitoring tool?

[John R Pierce]

Ivan Levchenko wrote:
> I'm already using cacti, but its not very usable, especially the
> notifications (or lack of them) and either i didn't find a way, or
> cacti cannot monitor services (http, smtp, others....)
>   

Nagios is for alerts and notifications, Cacti is for graphing trends.    
While either can be forced into the other role, each is best at it does 
natively.