Two, hours of attempting to get cacti to work have led me to be underimpressed with the whole project.
That's odd because other than the usual php version issues I've always considered cacti to be the easiest of the graphing tools to get working
- but I haven't tried the most recent versions.
Last I looked at Cacti, the hack to get some plugin support didn't work for me and I didn't have the patience to waste time with it, dropped it.
Munin never had zooming graphs, and needed a cgi to prevent obscene load in anything other than a trivial environment, dropped it.
I have Nagios and PNP and it works well. Since your first reco to me about OpenNMS I have been intrigued, it looks like a very nice project and is very active. Ironically I do almost all my Nagios monitoring via snmp and where I can't normally use snmp, I create extends...
If you are willing to hack some ugly-looking xml files that specify the oids and time intervals you can probably make opennms work for you - and you might find its other features (thresholding, notifications, etc.) useful too.
Yeah, I also want to take the time to learn this package, it does look very powerful.
Whit, if you are starting from scratch, I would second the reco to invest the time in OpenNMS and just learn something solid from day one.
jlc