ASR9K SNMP OID Changes

[IBEngTeam]

Hi all.

We monitor an ASR9K BFD and ISIS status using snmp. The issue is that each time the BFD or ISIS session drops and comes up, then the OID changes.

For BFD we use the ciscoBfdSessEntry, and for ISIS we use the isisISAdjState.

This is the snmp configuration:

snmp-server community xxx RO SystemOwner IPv4 xxx
snmp-server ifmib ifalias long
snmp-server ifindex persist
snmp-server ifmib stats cache
snmp-server trap link ietf
snmp-server mibs cbqosmib persist
snmp-server entityindex persist

Any ideas on what can be the issue and how to resolve?

Regards,

Adi.

[smilstea · Accepted solution]

I did some research on this today and the functionality you are looking for was added as a CLI knob in 4.0.1 via CSCtc05257 for BFD.

x

RP/0/RP0/CPU0:CRS-B#conf t
RP/0/RP0/CPU0:CRS-B(config)#bfd
RP/0/RP0/CPU0:CRS-B(config-bfd)#trap singlehop pre-mapped

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 482778
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745795 = administrativelyDown(8)
ciscoBfdSessDiag.2147745795 = administrativelyDown(8)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 482781
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745796 = administrativelyDown(8)
ciscoBfdSessDiag.2147745796 = administrativelyDown(8)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 482785
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745797 = administrativelyDown(8)
ciscoBfdSessDiag.2147745797 = administrativelyDown(8)

2) Bringing up bfd session with trap singlehop pre-mapped configured using bfd fast-detect under ospf

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 495967
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 496067
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 496069
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

3) Removing bfd fast-detect under ospf with trap singlehop pre-mapped under ospf and verifying non batched
traps are generated

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 507768
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 507769
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 507771
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

4) Checking that traps are batched for bfd session up event when trap singlehop pre-mapped is not configured.
Here traps are generated for dicriminator value 2147745798 to 2147745800.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 514068
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)

5) Checking that traps are batched for bfd session down event when trap singlehop pre-mapped is not configured.
Here traps are generated for dicriminator value 2147745798 to 2147745800.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 569768
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 576468
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)

6) Again checking that traps are non batched when trap singlehop pre-mapped is configured for three interfaces.
The session down event is triggered by removing bfd fast-detect in the global config in ospf for three interfaces.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 582868
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 582870
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 582871
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

7) Same test as 6 for bfd session up event. Re configuring bfd fast-detest in ospf global config

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 597168
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 597170
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 597172
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 633706
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 633707
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 633709
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

Unconfiguring trap singlehop pre-mapped and checking the bfd session up event, it should not display ifindex.
address type and session address.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1382530
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1382730
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1382730
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)

9) Reconfiguring trap singlehop pre-mapped and verifying that ifindex, address type and session address
are displayed.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1400230
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1400230
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1400231
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1403130
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1403130
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1403131
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

10) Process restart of bfd and then checking session down event when trap singlehop pre-mapped is unconfigured.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1416330
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)

11) Same test as 10 for bfd session up.

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1421130
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)

12) Process restart of bfd and then checking session down event when trap singlehop pre-mapped is configured

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1427930
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1427931
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1427931
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

13) Process restart of bfd and then checking bfd session up event when trap singlehop pre-mapped is configured
Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1451230
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1451330
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessDiag.2147745799 = noDiagnostic(1)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1451331
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1458690
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745798 = 26
ciscoBfdSessAddrType.2147745798 = ipv4(1)
ciscoBfdSessAddr.2147745798 = c0 a8 01 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1458691
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745799 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745799 = 27
ciscoBfdSessAddrType.2147745799 = ipv4(1)
ciscoBfdSessAddr.2147745799 = c0 a8 02 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1458691
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)
ciscoBfdSessInterface.2147745800 = 28
ciscoBfdSessAddrType.2147745800 = ipv4(1)
ciscoBfdSessAddr.2147745800 = c0 a8 03 02

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1470590
snmpTrapOID.0 = ciscoBfdSessUp
ciscoBfdSessDiag.2147745798 = noDiagnostic(1)
ciscoBfdSessDiag.2147745800 = noDiagnostic(1)

Received SNMPv2c Trap:
Community: public
From: 10.70.108.20
sysUpTimeInstance = 1475508
snmpTrapOID.0 = ciscoBfdSessDown
ciscoBfdSessDiag.2147745798 = neighborSignaledSessionDown(4)
ciscoBfdSessDiag.2147745800 = neighborSignaledSessionDown(4)

Here is what I found on ISIS.

Note that both isisCircIndex and isisISAdjIndex are needed to uniquely identify an entry in the table. A single interface may have adjacencies to multiple neighbors (think of a LAN) and to the same neighbor at multiple levels.

So, in the snmpwalk output of 1.3.6.1.2.1.138.1.6.1.1.2.48.11 :

 .2 shows isisAdjState

.48 shows interface ifindex  (same as isisCircIndex )

.11 stands for isisISAdjIndex

isisCircIndex (which has the same value as ifindex) and isisISAdjIndex. The isisISAdjIndex is assigned by ISIS to uniquely identify the per-level adjacency to a neighbor.

From RFC 4444:

-- The IS Adjacency Table
--
-- Each adjacency to an IS corresponds to one entry in this
-- table.

isisISAdjTable OBJECT-TYPE
SYNTAX SEQUENCE OF IsisISAdjEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table of adjacencies to Intermediate Systems."
::= { isisISAdj 1 }

isisISAdjEntry OBJECT-TYPE
SYNTAX IsisISAdjEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry corresponds to one adjacency to an
Intermediate System on this system.

Dynamically learned rows do not survive an agent reboot."
INDEX { isisCircIndex,
isisISAdjIndex }
::= { isisISAdjTable 1 }

I hope that those unit tests and explanations help with what you need.

Sam

[IBEngTeam]

Hi Sam,

Thanks for the detail and professional response.

This resolved my issue.

Adi.