With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fgHaStatsEntry
fg Ha Stats Entry
1.3.6.1.4.1.12356.101.13.2.1.1
Statistics for a particular HA cluster's unit
Back to FORTINET-FORTIGATE-MIB MIB page.
IPHost Network monitor allows you to monitor fgHaStatsEntry on Fortinet device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Fortinet WAN extenders right now.