I was just working to get some OIDs myself for routing, sorry it's probably late, but:
At least on my FortiGate 30E the OID for ipRouteTable is:
See attached image, I've highlighted what I used to trigger my Operation's Manager alert. (If NextHop changes - then alert). The OID is .126.96.36.199.188.8.131.52.1.7 and then you append the IP to the route, for instance for last resort: .184.108.40.206.220.127.116.11.18.104.22.168.0.0 - the value shall be the NextHop IP according to the route table.
I did exactly what you wrote @seshuganesh, I also compiled along "FORTINET-CORE-MIB.mib" && "FORTINET-FORTIGATE-MIB.mib" (both version 7.2.5) the "FortiAnalyzer-" and "Manager"-mibs (both version 7.2.3), but still get the output that some OIDs are not assigned to a name, f.e.:
Trap Detail: fnSysSerial:
Can you guys recommend any mib package from a certain year or version to solve this problem?
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