With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnExtDeletedPDPs
cisco Gateway GPRS Support Node Ext Deleted PD Ps
1.3.6.1.4.1.9.9.647.1.1.15.1.4
This object indicates the number of PDP contexts deleted in the last sampling period specified by cGgsnExtCallRateInterval.
Back to CISCO-GGSN-EXT-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnExtDeletedPDPs 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.