With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fnFirewallIPMACState
fn Firewall IPMAC State
1.3.6.1.4.1.12356.2.7.1.1.5
The state of the the IPMAC binding entry
Back to FORTINET-MIB MIB page.
IPHost Network monitor allows you to monitor fnFirewallIPMACState on Fortinet device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Fortinet firewalls right now.