With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ciscoUnityPortsOutboundActive
cisco Unity Ports Outbound Active
1.3.6.1.4.1.9.9.385.1.2.7
The number of outbound ports that are currently active with calls.
Back to CISCO-UNITY-MIB MIB page.
IPHost Network monitor allows you to monitor ciscoUnityPortsOutboundActive on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco multiplexers right now.