With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fnUserAuth
fn User Authorization
1.3.6.1.4.1.12356.1.102.2.1.3
Authentication type of the account
Back to FORTINET-MIB-280 MIB page.
IPHost Network monitor allows you to monitor fnUserAuth 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.