FortiOS v6.4.3 build1778 - problem with SNMPv3

Again , did you read what I posted earlier ?

If you want to do noAuthnoPriv for 1st stage testing and elimination

Your problem is 100% authentication related. You have to test and eliminate that. Setup a basic snmp users with no authentication or priv and test. Doe sit work ? If yes? Add on auth and retest if it does not work, perform the corrective action and proceed.

e.g 

config system snmp user edit "adminkfelix" set status enable set trap-status enable  set queries enable

# fo a 1st stage test  set security-level no-auth-no-priv next end

And then do a simple walk.

secenginfobankgrupo@socpuppets:~$ snmpwalk -v 3 -u adminkfelix  192.168.199.12     .1.3.6.1.2.1.47.1.2.1.1.2.1 iso.3.6.1.2.1.47.1.2.1.1.2.1 = STRING: "Fortinet Firewall FortiGate-100E v6.4.4,build1803,201209 (GA)"

If you do that and it works, than add in   auth-no-priv  and then auth-priv . Ensure your using the correct type

e.g

secenginfobankgrupo@socpuppets:~$ snmpwalk -v 3 -u adminkfelix -l authNoPriv -a SHA -A test1234567890 1 92.168.199.12  .1.3.6.1.2.1.47.1.2.1.1.2.1 iso.3.6.1.2.1.47.1.2.1.1.2.1 = STRING: "Fortinet Firewall FortiGate-100E v6.4.4,build1803,201209 (GA)"

for diagnostics fortiOS

diag debug reset 

diag debug enable

diag debug application snmpd -1

if you see " (USM authentication failure)" in the diagnostic again that means something wrong with authentication.

If you see  (unknown user name), than that's a clue your user is incorrect. But since you have USM issues ( from your earlier post)  your aes/3des or md5/sha is incorrect for that user. So the simplest means is to correct it or go thru the process of elimination.

Also be advise some snmp-NMS do not support MD5 so ensure the snmp-prober is correct or use snmp-utilility pkg in  a unix or linux systems. And some clients are des only so , upgrade that system. You should be using AES imho and SHA if possible.

Ken Felix