I'm using Cacti (http://www.cacti.net) to monitor a number of my network devices and graph things like Interface Statistics. One area where I've had problems is Graphing channel usage on my PRI's in my Cisco 3825 Voice Gateway router. I'm sure my problems are probably related to my lack of understanding of SNMP and the fact that I've not found a good device template for the 3825 for Cacti. So I'm using a Generic Template that simply gives me the individual channels and dial-peers (see attached PDF), but nothing that would be useful for total channel usage. I'm looking for something similar to what is in Cisco's RTMT tool (Calls in Progress).
Any thoughts anyone???