Hi,
We have been having multiple bfd flapping on a TenGig interface on our Cisco ASR9000 (v6.2.3). This has been happening for few weeks now. Issue usually occurs once everyday at random timestamp within 5 to 20mins downtime.
Below are the sample logs.
LC/0/0/CPU0:2019 Oct 4 08:45:14.693 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_DOWN : BFD session to neighbor on interface TenGigE0/0/0/18 has gone down. Reason: Nbor signalled down
RP/0/RSP0/CPU0:2019 Oct 4 08:45:14.695 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
RP/0/RSP1/CPU0:2019 Oct 4 08:45:14.694 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
RP/0/RSP0/CPU0:2019 Oct 4 08:45:15.716 FJT: ipv4_rib[1168]: %ROUTING-RIB-7-SERVER_ROUTING_DEPTH : Recursion loop looking up prefix 202.137.178.3 in Vrf: "default" Tbl: "default" Safi: "Unicast" added by bgp
RP/0/RSP1/CPU0:2019 Oct 4 08:45:15.722 FJT: ipv4_rib[1168]: %ROUTING-RIB-7-SERVER_ROUTING_DEPTH : Recursion loop looking up prefix 202.137.178.3 in Vrf: "default" Tbl: "default" Safi: "Unicast" added by bgp
LC/0/0/CPU0:2019 Oct 4 08:45:18.512 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_ON : Session to neighbor on interface TenGigE0/0/0/18 entered Dampened state (initial: 2000 ms,secondary: 5000 ms,maximum: 120000 ms).
RP/0/RSP0/CPU0:2019 Oct 4 08:45:18.553 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Up, New adjacency
RP/0/RSP1/CPU0:2019 Oct 4 08:45:18.553 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Up, New adjacency
LC/0/0/CPU0:2019 Oct 4 08:45:20.513 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_OFF : Session to neighbor on interface TenGigE0/0/0/18 moved out of Dampened state.
LC/0/0/CPU0:2019 Oct 4 08:45:20.513 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_UP : BFD session to neighbor on interface TenGigE0/0/0/18 is up
LC/0/0/CPU0:2019 Oct 4 08:45:57.488 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_DOWN : BFD session to neighbor on interface TenGigE0/0/0/18 has gone down. Reason: Control timer expired
RP/0/RSP0/CPU0:2019 Oct 4 08:45:57.490 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to SUV-ISP-COR-001 (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
RP/0/RSP1/CPU0:2019 Oct 4 08:45:57.489 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
LC/0/0/CPU0:2019 Oct 4 08:46:02.022 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_ON : Session to neighbor on interface TenGigE0/0/0/18 entered Dampened state (initial: 2000 ms,secondary: 5000 ms,maximum: 120000 ms).
RP/0/RSP0/CPU0:2019 Oct 4 08:46:02.062 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Up, New adjacency
RP/0/RSP1/CPU0:2019 Oct 4 08:46:02.061 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Up, New adjacency
LC/0/0/CPU0:2019 Oct 4 08:46:07.673 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_OFF : Session to neighbor on interface TenGigE0/0/0/18 moved out of Dampened state.
LC/0/0/CPU0:2019 Oct 4 08:46:07.673 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_UP : BFD session to neighbor on interface TenGigE0/0/0/18 is up
LC/0/0/CPU0:2019 Oct 4 08:46:58.589 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_DOWN : BFD session to neighbor on interface TenGigE0/0/0/18 has gone down. Reason: Control timer expired
RP/0/RSP1/CPU0:2019 Oct 4 08:46:58.590 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
RP/0/RSP0/CPU0:2019 Oct 4 08:46:58.591 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Down, BFD session DOWN
LC/0/0/CPU0:2019 Oct 4 08:47:05.978 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_ON : Session to neighbor on interface TenGigE0/0/0/18 entered Dampened state (initial: 2000 ms,secondary: 5000 ms,maximum: 120000 ms).
RP/0/RSP0/CPU0:2019 Oct 4 08:47:06.019 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to neighbor (TenGigE0/0/0/18) (L2) Up, New adjacency
RP/0/RSP1/CPU0:2019 Oct 4 08:47:06.018 FJT: isis[1010]: %ROUTING-ISIS-5-ADJCHANGE : Adjacency to nieghbor (TenGigE0/0/0/18) (L2) Up, New adjacency
LC/0/0/CPU0:2019 Oct 4 08:47:13.738 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_DAMPENING_OFF : Session to neighbor on interface TenGigE0/0/0/18 moved out of Dampened state.
LC/0/0/CPU0:2019 Oct 4 08:47:13.778 FJT: bfd_agent[126]: %L2-BFD-6-SESSION_STATE_UP : BFD session to neighbor on interface TenGigE0/0/0/18 is up
What could be the root cause and solution to this ?
Appreciate your feedback.
