With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cpimExtMRouteEntry
cpim Ext M Route Entry
1.3.6.1.4.1.9.10.120.1.1.4.1
An entry (conceptual row) in the cpimExtIPMRouteTable. There is one entry per entry in the cIpMRouteTable whose incoming interface is running PIM.
Back to CISCO-IETF-PIM-EXT-MIB MIB page.
IPHost Network monitor allows you to monitor cpimExtMRouteEntry on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.