Timeout on snmpwalk

[Exo]

Hello,

I've noticed a strange problem on a new FortiOS 5.6.3, FortiGate 60E.

I'm trying to monitor, thanks to SNMP, my wan traffic Bandwidth. I'm using Centreon monitoring system.

The script that I used is working on other Fortigate (80D, 60D and 30E).

When I used this script i've got a "UNKNOWN: SNMP GET Request : Timeout" error.

When I do a "snmpwalk -v 2c -c my_community [my_public_ip_address]" I can go trough all the OIDs allways until this OID "EtherLike-MIB::dot3ControlInUnknownOpcodes.17". For exemple :

# snmpwalk -v 2c -c my_community [my_public_ip_address]
SNMPv2-MIB::sysDescr.0 = STRING:
SNMPv2-MIB::sysObjectID.0 = OID: SNMPv2-SMI::enterprises.12356.101.1.641
DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (10257880) 1 day, 4:29:38.80
SNMPv2-MIB::sysContact.0 = STRING:

[...]

EtherLike-MIB::dot3ControlInUnknownOpcodes.13 = Counter32: 0
EtherLike-MIB::dot3ControlInUnknownOpcodes.14 = Counter32: 0
EtherLike-MIB::dot3ControlInUnknownOpcodes.15 = Counter32: 0
EtherLike-MIB::dot3ControlInUnknownOpcodes.16 = Counter32: 0
EtherLike-MIB::dot3ControlInUnknownOpcodes.17 = Counter32: 0
Timeout: No Response from [my_public_ip_address]

When I do a "snmpwalk -v 2c -c my_other_community [my_other_public_ip_address]" on my other FortiGate I can go trough all the OIDs whitout error.

All my other Centreon check (CPU, RAM, Session) on my 60E are working perfectly.

It's the only 60E Fortigate that i'll have, but my others FortiGate in 5.6.3 OS are working well.

The SNMP is enable and correctly configure. On my WAN interface the SNMP is enable : otherwise I think that I can't run a snmpwalk at all.

I don't think that my public interface is not working well because I'm always stuck on the same OID...

Is somebody know how to resolve this issue or have an idea ?

Thanks.

[emnoc]

Good find and I learned something new.  I wonder if  you re-try to duplicate the snmpIfIndex  on a 3rd interface would the FortIOS allow this? Could be a bug or something odd in  v5.6.3.