Hi Community,
before deployment, we are testing SNMPv3 Informs notifications in AuthPriv mode.
Tests with IOS, IOS-XE and NX-OS were successful.
Unfortunately, configuration in IOS-XRv (Version 7.2.1) is not working correctly. Probably an configuration error.
This is the IOS-XRv config (with all parameters same for all tested platforms):
snmp-server engineID remote [redacted-IP] 80:00:1f:88:04:56:6e:65:74:5a:61:62 udp-port 162
snmp-server vrf default
host [redacted-IP] informs version 3 priv zabbixtrap
!
snmp-server user zabbixtrap TESTgroup remote [redacted-IP] v3 auth sha encrypted [redacted-AUTH] priv aes 128 encrypted [redacted-PRIV]
snmp-server view ViewDefault iso included
snmp-server group TESTgroup v3 priv notify ViewDefault
snmp-server traps snmp linkup
snmp-server traps snmp linkdown
snmp-server traps snmp coldstart
snmp-server traps snmp warmstart
snmp-server traps system
snmp-server traps fru-ctrl
snmp-server ifindex persist
snmp-server mibs cbqosmib persist
!
With issued # debug snmp packets this is the output:
ifmgr[296]: %PKT_INFRA-LINK-5-CHANGED : Interface GigabitEthernet0/0/0/3, changed state to Administratively Down
snmpd[1003]: t9159 snmp_get_table_id_from_vrfid: TableID 0xE0000000 VrfID 0x60000000
snmpd[1003]: t9159 Successfully got vrf_id:1610612736 and table_id:-536870912 for vrf:default
snmpd[1003]: t9159 snmp_is_dst_address_reachable:Successfully got src address:10.201.254.253 to dest:10.201.254.253 in vrf:default, vrf_id:1610612736, ifhandle:0x1000018
snmpd[1003]: t9159 Src address updated as :10.201.254.253
snmpd[1003]: t9159 snmp_get_table_id_from_vrfid: TableID 0xE0000000 VrfID 0x60000000
snmpd[1003]: t9159 Successfully got vrf_id:1610612736 and table_id:-536870912 for vrf:default
snmpd[1003]: t9159 snmp_is_dst_address_reachable:Successfully got src address:10.201.254.253 to dest:10.201.254.253 in vrf:default, vrf_id:1610612736, ifhandle:0x1000018
snmpd[1003]: t9159 Src address updated as :10.201.254.253
snmpd[1003]: t9159 snmp_send_pdu_udp_transport: Q-ing INFORM[sp 162, dp 41472]
snmpd[1003]: t9187 SENT[I] 81 bytes to [redacted-IP]:162 from 10.201.254.253:162, vrfid 0x60000000, tblid 0xe0000000
snmpd[1003]: t9178 RECV Inform response 114 bytes from [redacted-IP]:162 to 10.201.254.253, vrfid 0x60000000, tblid 0xe0000000
snmpd[1003]: t9178 snmp_get_inform_response_id: SrParseSnmpMessage error_code = 602
snmpd[1003]: t9178 ERROR: Inform response pdu type -168 request-id 183 error_status = 0 error_index = 0
After the Timeout period, this packet exchange is repeated according to "Inform Retries" count integer.
I'm also attaching screens from WireShark captures of sent and received packets between router-VM and NMS (Zabbix NMS with Net-SNMP's snmptrapd)
Sent SNMPv3 packet (from IOS-XRv):
Received SNMPv3 packet (from snmptrapd):
For examples and comparison, this vIOS configuration worked as expected:
snmp-server engineID remote [redacted-IP] 80001f8804566e65745a6162
snmp-server group TESTgroup v3 priv
snmp-server user zabbixtrap TESTgroup remote [redacted-IP] v3 auth sha [redacted-AUTH] priv aes 128 [redacted-PRIV]
snmp-server ifindex persist
snmp-server enable traps snmp linkdown linkup coldstart warmstart
snmp-server inform
snmp-server host [redacted-IP] informs version 3 priv zabbixtrap
!
Also working CSR1000v (IOS-XE) example config:
snmp-server engineID remote [redacted-IP] 80001F8804566E65745A6162
snmp-server view ViewDefault iso included
snmp-server group TESTgroup v3 priv notify ViewDefault
snmp-server user zabbixtrap TESTgroup remote [redacted-IP] v3 auth sha [redacted-AUTH] priv aes 128 [redacted-PRIV]
snmp-server enable traps snmp linkdown linkup coldstart warmstart
snmp-server inform
snmp-server host [redacted-IP] informs version 3 priv zabbixtrap
snmp ifmib ifindex persist
!
For comparison, I'm attaching working SNMPv3 Inform packet exchange:
Sent SNMPv3 packet (from vIOS):
Received SNMPv3 packet (from snmptrapd):
Thank you for your time and attention. Of course, I'm open for further questions. Any help or direction would be much appreciated.
Best Regards,
Vincent Vlk
