With IPHost Network Monitor you can run simple snmp requests against a Fortinet device in your network.
fnHaStatsNetUsage
fn Ha Stats Net Usage
1.3.6.1.4.1.12356.1.100.6.1.5
Network Usage of HA Cluster's unit
Back to FORTINET-MIB-280 MIB page.
IPHost Network monitor allows you to monitor fnHaStatsNetUsage 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.
