troubleshout BGP

Owned by Jean-luc KRIKER
Last updated: May 07, 2024
6 min read





debug bgp events

terminal monitor / terminal no monitor
on R22024 Apr 19 06:54:00.469 : uk-wnlb-lg-pol-cin-02 : BGP : ERROR : 10.10.100.4-Incoming [DECODE] Open: Invalid Router ID 10.10.100.2
. . .
2024 Apr 19 06:54:00.469 : uk-wnlb-lg-pol-cin-02 : BGP : ERROR : 10.10.100.4-Outgoing [DECODE] Open: Invalid Router ID 10.10.100.2
on R42024 May 07 11:08:34.891 : uk-wnlb-lg-pol-cin-04 : BGP : ERROR : 10.10.100.2-Outgoing [DECODE] Open: Invalid Router ID 10.10.100.2
2024 May 07 11:08:39.893 : uk-wnlb-lg-pol-cin-04 : BGP : ERROR : 10.10.100.2-Incoming [DECODE] Open: Invalid Router ID 10.10.100.2


on R2
show bgp summary
uk-wnlb-lg-pol-cin-02#show bgp summary
BGP router identifier 10.10.100.2, local AS number 65002  >>>>>>> RouterID ok <<<<<<<<<<< 
BGP table version is 1
0 BGP AS-PATH entries
0 BGP community entries

Neighbor                 V   AS   MsgRcv    MsgSen TblVer   InQ   OutQ    Up/Down   State/PfxRcd
10.10.100.1              4 65002 12960
                                                 12988       1      0      0  00:24:16               0
10.10.100.3              4 65002 12980
                                                 12984       1      0      0  00:24:16               0
10.10.100.4              4 65002 65971
                                                135981       0      0      0     never        Idle

Total number of neighbors 3


uk-wnlb-lg-pol-cin-02#show bgp neighbors 10.10.100.4
BGP neighbor is 10.10.100.4, remote AS 65002, local AS 65002, internal link, peer index: 4
  BGP version 4, local router ID 10.10.100.2, remote router ID 0.0.0.0  <<<<<< no Router ID >>>>>
  BGP state = Idle
  Last read Never, hold time is 90, keepalive interval is 30 seconds
  Received 65984 messages, 0 notifications, 0 in queue
  Sent 70024 messages, 65984 notifications, 0 in queue
  Route refresh request: received 0, sent 0
  Minimum time between advertisement runs is 5 seconds
  Update source is lo

For address family: IPv4 Unicast  BGP table version 1, neighbor version 0
  Index 3, Offset 0, Mask 0x8
  AIGP is enabled
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  0 announced prefixes


For address family: VPNv4 Unicast  BGP table version 1, neighbor version 0
  Index 3, Offset 0, Mask 0x8
  AIGP is enabled
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  0 announced prefixes


For address family: L2VPN EVPN  BGP table version 1, neighbor version 0
  Index 3, Offset 0, Mask 0x8
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  Accepted AD:0 MACIP:0 MCAST:0 ESI:0 PREFIX:0
  0 announced prefixes

 Connections established 0; dropped 0
TCP MSS: (0), Advertise TCP MSS: (0), Send TCP MSS: (536),  Receive TCP MSS: (0)
Sock FD : (28)
Last Reset: 00:00:02, due to OPEN Message Error (Notification sent)
Notification Error Message: (OPEN Message Error/Bad BGP Identifier. Reason:  <<<<< Bad BGP ID >>>>>>

d)

show bgp summary
uk-wnlb-lg-pol-cin-04#show bgp summary
BGP router identifier 10.10.100.2, local AS number 65002   >>>>>>> Router ID is wrong !!!! <<<<<<<< 
BGP table version is 1
0 BGP AS-PATH entries
0 BGP community entries

Neighbor                 V   AS   MsgRcv    MsgSen TblVer   InQ   OutQ    Up/Down   State/PfxRcd
10.10.100.1              4 65002 12891
                                                 12899       1      0      0  00:17:26               0
10.10.100.2              4 65002 65992
                                                133785       0      0      0     never        Idle
10.10.100.3              4 65002 12895
                                                 12897       1      0      0  00:17:26               0

Total number of neighbors 3

Total number of Established sessions 2
uk-wnlb-lg-pol-cin-04#show bgp neighbors 10.10.100.2
BGP neighbor is 10.10.100.2, remote AS 65002, local AS 65002, internal link, peer index: 2
  BGP version 4, local router ID 10.10.100.2, remote router ID 0.0.0.0
  BGP state = Idle
  Last read Never, hold time is 90, keepalive interval is 30 seconds
  Received 65994 messages, 0 notifications, 0 in queue
  Sent 67795 messages, 65994 notifications, 0 in queue
  Route refresh request: received 0, sent 0
  Minimum time between advertisement runs is 5 seconds
  Update source is lo

For address family: IPv4 Unicast  BGP table version 1, neighbor version 0
  Index 1, Offset 0, Mask 0x2
  AIGP is enabled
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  0 announced prefixes


For address family: VPNv4 Unicast  BGP table version 1, neighbor version 0
  Index 1, Offset 0, Mask 0x2
  AIGP is enabled
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  0 announced prefixes


For address family: L2VPN EVPN  BGP table version 1, neighbor version 0
  Index 1, Offset 0, Mask 0x2
  Community attribute sent to this neighbor (both)
  Large Community attribute sent to this neighbor
  0 accepted prefixes
  Accepted AD:0 MACIP:0 MCAST:0 ESI:0 PREFIX:0
  0 announced prefixes

 Connections established 0; dropped 0
TCP MSS: (0), Advertise TCP MSS: (0), Send TCP MSS: (536),  Receive TCP MSS: (0)
Sock FD : (28)
Last Reset: 00:00:01, due to OPEN Message Error (Notification sent)
Notification Error Message: (OPEN Message Error/Bad BGP Identifier. Reason:

d)

uk-wnlb-lg-pol-cin-04#
restart process
on R4router bgp 65002
bgp router-id 10.10.100.4