SNMPv3 Not able to discover device in BMC application

[CCIEKW-HOTMAIL]

SNMPv3 Not able to discover device in BMC application.

I have enable on Interface SNMP, Username password created and SNMPv3 enabled .

SNMP walk is not able to get the output.

[AEK]

Here is the config that works for me on FWB VM 7.4.10. Try the same and see if it helps.

Then snmpwalk from 192.168.71.1 (the allowed host).

$ snmpwalk -v3 -u snmp1 -l authNoPriv -a sha -A 'Passwd-123' 192.168.71.3 
iso.3.6.1.2.1.1.1.0 = ""
iso.3.6.1.2.1.1.2.0 = OID: iso.3.6.1.4.1.12356.107.1.50006
iso.3.6.1.2.1.1.3.0 = Timeticks: (107559) 0:17:55.59
iso.3.6.1.2.1.1.4.0 = ""
iso.3.6.1.2.1.1.5.0 = STRING: "FortiWeb"
iso.3.6.1.2.1.1.6.0 = ""
iso.3.6.1.2.1.1.7.0 = INTEGER: 0
iso.3.6.1.2.1.1.9.1.1.1 = INTEGER: 1
iso.3.6.1.2.1.1.9.1.2.1 = OID: ccitt.0.0
...

Hope it helps.

[CCIEKW-HOTMAIL]

I am facing the issue that traffic is getting blocked from outside to inside.

[AEK]

Then this is another issue.

Did you use a VIP to map External_IP:161 to Internal_IP:161 (UDP), and added a firewall rule to allow traffic from external to VIP?

However know that SNMP is not intended to be published on the WAN. I don't think it is safe to do so, unless you allow only from specific source.

[CCIEKW-HOTMAIL]

Yes, i think some rules are missing from External to internal as i have some other devices on which it is working fine. 

[AEK]

You can check it with policy lookup.

https://community.fortinet.com/t5/FortiGate/Technical-Tip-Firewall-policy-lookups/ta-p/192912

[CCIEKW-HOTMAIL]

When I try the destination from the mgmt1 source, it is not reaching, but globally it is reaching. 

[AEK]

Did you say from outside/external or from mgmt1, or both?

Can you share a screenshot of the related policy with mgmt1 as source intf?