With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fnSysConfigAdminUserNetmask
fn Sys Config Admin User Netmask
1.3.6.1.4.1.12356.1.4.3.1.1.4
Admin user netmask
Back to FORTINET-MIB MIB page.
IPHost Network monitor allows you to monitor fnSysConfigAdminUserNetmask 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.