With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
alL2tpStatsTunnelPeerIpAddr
ALTIGA L2tp Statistics Tunnel Peer Ip Address
1.3.6.1.4.1.3076.2.1.2.16.2.1.2
The peer's IP address for this tunnel.
Back to ALTIGA-L2TP-STATS-MIB MIB page.
IPHost Network monitor allows you to monitor alL2tpStatsTunnelPeerIpAddr on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.