With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cagwDhcpReleasePackets
Cisco's ASN Gateway Dhcp Release Packets
1.3.6.1.4.1.9.9.638.1.3.2.1.1.7
The number of DHCP Release packets transmitted by the DHCP relay in the ASN-GW to the DHCP server.
Back to CISCO-ASN-GATEWAY-MIB MIB page.
IPHost Network monitor allows you to monitor cagwDhcpReleasePackets 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.