thanx a lot, but may i ask :
0. from what i have googled so far, the best thing to do is to have cacti polling the data, and then, through passive interfaces, feed these data in Nagios. is that correct ?
1. why is the above a better solution than having nagios actively polling the devices and fill in the records in the rrd_tool ?
2. and last, which is the simplest way of plotting the statistics in real-time (without requesting the plots) ?
thank you in advance