With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fnVpnDialupMonProxyIdSrc
fn Vpn Dialup Monitor Proxy Id Source
1.3.6.1.4.1.12356.4.1.6.1.5
actual IP address or subnet address of the remote peer
Back to FORTINET-MIB MIB page.
IPHost Network monitor allows you to monitor fnVpnDialupMonProxyIdSrc on Fortinet device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Fortinet switches right now.