Technical Tip: Monitoring the memory usage on FortiGates

[aionescu]

Description

This article describes the different OIDs available to monitor memory consumption on FortiGates.

Solution

It is possible to use the below 2 OIDs to monitor the current memory usage on FortiGate.

•  fgSysMemUsage (.1.3.6.1.4.1.12356.101.4.1.4.0) - shows the amount of used memory, as displayed in the command 'get system performance status'.
•  fgHaStatsMemUsage (.1.3.6.1.4.1.12356.101.13.2.1.1.4) - same as fgSysMemUsage, but for the FortiGates on HA.

FGT # get system performance status
CPU states: 1% user 1% system 0% nice 98% idle 0% iowait 0% irq 0% softirq
CPU0 states: 1% user 1% system 0% nice 98% idle 0% iowait 0% irq 0% softirq
Memory: 2042080k total, 1115588k used (54.6%), 579212k free (28.4%), 347280k freeable (17.0%)

FortiGate can send SNMP trap if the memory usage is higher than 80% (default), this value can be modified using the below configuration.

config system snmp sysinfo
    set status enable
    set trap-low-memory-threshold 85
end

Related Articles:

Technical Tip: How to Configure FortiGate SNMP Agent for Monitoring