Monitoring the BGP Routing Table

Purpose

Display the BGP IPv4 routing table or BGP IPv6 routing table.

The show ip bgp and show bgp ipv6 commands display similar information.

Action

To display information about routes in the IPv6 multicast address family:

host1#show bgp ipv6 multicast
Local BGP identifier 10.13.13.13, local AS 400
  4 routes (160 bytes)
  4 destinations (288 bytes) of which 4 have a route
  4 routes selected for route table installation
  3 path attribute entries (456 bytes)
  Local-RIB version 31. FIB version 31.
 
Status codes: > best, * invalid, s suppressed, d dampened, r rejected,
              a auto-summarized
 
  Prefix                  Peer            Next-hop               MED  LocPrf   Weight  Origin
  ::103.103.103.0/120     103.103.103.3   ::103.103.103.3        0             0       inc.   
> 3ffe:0:0:1::/64         11.11.11.11     ::101.101.101.1        0    100      0       inc.   
> 3ffe:0:0:3::/64         103.103.103.3   ::103.103.103.3        0             0       inc.   
> 3ffe:0:1:1::/64         12.12.12.12     ::102.102.102.2        0    100      0       inc.   

To display information about routes for the specified IPv4 prefix:

host1:pe1#show ip bgp 10.88.88.1
BGP route information for prefix 10.88.88.1/32
  Network route (best route
    Advertised to both internal and external peers
    Address Family Identifier (AFI) is ip-v4
    Subsequent Address Family Identifier (SAFI) is unicast
    Next hop IP address is 0.0.0.0 (metric 2)
    Multi-exit discriminator is 1
    Local preference is not present
    Weight is 32768
    Origin is IGP
    AS path is empty
    Extended communities empty

To display information about routes for the specified IPv6 prefix:

host1:pe1#show bgp ipv6 2001:0430::1/128

BGP route information for prefix 2001:1::1/128
  Received route learned from internal peer 2.2.2.2 (best route)
    Route placed in IP forwarding table
    Best to advertise to external peers
    Address Family Identifier (AFI) is ip-v6
    Subsequent Address Family Identifier (SAFI) is unicast
    MPLS in-label is none
    MPLS out-label is 17
    Next hop IP address is ::ffff:2.2.2.2 (metric 3)
    Multi-exit discriminator is 0
    Local preference is 100
    Weight is 0
    Origin is IGP
    AS path is 65021

To display information about next hop routers for VRF PE 11 in the IPv4 VPN address family:

host1:pe1#show ip bgp vpnv4 vrf pe11 next-hops
Indirect next-hop 11.11.11.2
    Resolution in IP route table of VR pe11
Reachable (metric 0)
IP indirect next-hop index 35
Direct next-hop ATM2/0.11 (11.11.11.2)
    Resolution in IP tunnel-route table of VR pe11
        Not reachable
      Reference count is 1

Indirect next-hop 2.2.2.2
    Resolution in IP route table of VR pe1
IP indirect next-hop index 123
Reachable (metric 100)
    Direct next-hop POS4/0 (10.10.10.1)
                POS4/1 (12.12.12.1)

Resolution in IP tunnel-route table of VR pe1
MPLS indirect next-hop index 578
Reachable (metric 100)
    Direct next-hop Push 23, POS4/0 (10.10.10.1)
                Push 43, POS4/1 (12.12.12.1)

Reference count is 1

To display information about routes in the route-target address family:

host1:pe1#show ip bgp route-target signaling
Local BGP identifier 13.13.13.13, local AS 100
  4 routes (240 bytes)
  3 destinations (228 bytes) of which 3 have a route
  3 routes selected for route tables installation
  0 unicast/multicast routes selected for route table installation
  0 unicast/multicast tunnel-usable routes selected for route table installation
  0 tunnel-only routes selected for tunnel-route table installation
  10 path attribute entries (1520 bytes)
  Local-RIB version 19. FIB version 19.
Status codes: > best, * invalid, s suppressed, d dampened, r rejected,
              a auto-summarized
  Prefix             Peer            Next-hop         MED LocPrf Weight Origin
> 0:0:0/0            12.12.12.12     12.12.12.12             100      0 IGP
> 100:100:1/96       11.11.11.11     11.11.11.11             100      0 IGP
  100:100:1/96       14.14.14.14     14.14.14.14             100      0 IGP
> 100:100:2/96       11.11.11.11     11.11.11.11             100      0 IGP

To display information about routes in the route-target address family corresponding to the specified RT-MEM-NLRI:

host1:pe1#show ip bgp route-target signaling 100:100:1/96
BGP route information for prefix 100:100:1/96
  Received route learned from internal peer 11.11.11.11 (best route)
    Route not placed in IP forwarding table
    Best to advertise to both internal and external peers
    Address Family Identifier (AFI) is ip-v4
    Subsequent Address Family Identifier (SAFI) is route-target-signaling
    Next hop IP address is 11.11.11.11 (metric 0)
    Multi-exit discriminator is not present
    Local preference is 100
    Weight is 0
    Origin is IGP
    AS path is empty
  Received route learned from internal peer 14.14.14.14
    Route not placed in IP forwarding table
    Do not advertise to any peers
    Address Family Identifier (AFI) is ip-v4
    Subsequent Address Family Identifier (SAFI) is route-target-signaling
    Next hop IP address is 14.14.14.14 (metric 0)
    Multi-exit discriminator is not present
    Local preference is 100
    Weight is 0
    Origin is IGP
    AS path is empty

To display information about network routes in the route-target address family:

host1:pe1#show ip bgp route-target signaling network
Prefix             Weight Route-map                        Backdoor
102:111:34/96                                              No
1111111111:23:1/96                                         No

To display information about network routes in the route-target address family corresponding to the specified RT-MEM-NLRI:

host1:pe1#show ip bgp route-target signaling network 102:111:34
Prefix             Weight Route-map                        Backdoor
102:111:34/96                                              No

To display filtered information about all networks in the BGP routing table:

host1:pe1#show ip bgp fields peer next-hop next-hop-cost
Prefix             Peer            Next-hop      Next-hop-cost
11.11.11.11/32     3.3.3.3         3.3.3.3       Unreachable
11.11.11.11/32     4.4.4.4         4.4.4.4       Unreachable
22.22.22.22/32     3.3.3.3         3.3.3.3       Unreachable
22.22.22.22/32     4.4.4.4         4.4.4.4       Unreachable
33.33.33.33/32     3.3.3.3         3.3.3.3       Unreachable
44.44.44.44/32     4.4.4.4         4.4.4.4       Unreachable
55.55.55.55/32     0.0.0.0         0.0.0.0       0
66.66.66.66/32     6.6.6.6         6.6.6.6       Unreachable
77.77.77.77/32     57.57.57.7      57.57.57.7    1
88.88.88.88/32     57.57.57.7      57.57.57.7    1

To display filtered information about routes that are stale due to peer restart:

host1:pe1#show ip bgp fields best peer next-hop stale
Prefix             Stale Peer            Next-hop
10.22.22.1/32      stale 10.12.12.2      10.12.12.2
10.22.22.2/32      stale 10.12.12.2      10.12.12.2
10.22.22.3/32      stale 10.12.12.2      10.12.12.2
10.33.33.1/32            10.13.13.3      10.13.13.3
10.33.33.2/32            10.13.13.3      10.13.13.3
10.33.33.3/32            10.13.13.3      10.13.13.3 

To display introductory information about BGP attributes:

host1:pe1#show ip bgp 0.0.0.0 /0 fields intro
Local BGP identifier 192.168.254.79, local AS 6730
  201058 routes (12063492 bytes)
  201540 destinations (15317040 bytes) of which 201058 have a route
  193909 routes selected for route tables installation
  0 unicast/multicast routes selected for route table installation
  0 unicast/multicast tunnel-usable routes selected for route table     installation
  0 tunnel-only routes selected for tunnel-route table installation
  35097 path attribute entries (5334744 bytes)
  Local-RIB version 20969483. FIB version 20969483.
  Statistics baseline set WED JUL 12 2006 10:31:53 METDST
  ...

To display all routes with a prefix that is equal to or more specific than the specified prefix:

host1#show ip bgp 12.2.0.0 255.255.0.0 longer-prefixes
Local router ID 192.168.1.153, local AS 100
  72074 paths, 72074 distinct prefixes (5189328 bytes used)
  72074 paths selected for route table installation
  21685 path attribute entries (2965327 bytes used)

  Prefix         Peer       Next-hop   MED CalPrf  Weight  Origin
> 12.2.6.0/24    10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.7.0/24    10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.76.0/24   10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.88.0/22   10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.97.0/24   10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.99.0/24   10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.109.0/24  10.5.0.48  10.5.0.48    100         100     IGP
> 12.2.169.0/24  10.5.0.48  10.5.0.48    100         100     IGP

Meaning

Table 25 lists the show ip bgp command output fields.

Table 25: show ip bgp Output Fields

Field Name

Field Description

Local BGP identifier

BGP router ID of the local router

local AS

Local autonomous system number

routes

Total number of routes stored in the BGP routing table and amount of memory consumed by routes. If several peers have advertised a route to the same prefix, all routes are included in this count.

destinations

Number of routes to unique prefixes stored in the BGP routing table and amount of memory consumed by routes. If several peers have advertised a route to the same prefix, only the best route is included in this count.

routes selected for route table installation

Number of routes in the BGP routing table that have been inserted into the IP routing table, plus prefixes for which there are currently no routes but which have had to be withdrawn from peers to which these prefixes may been previously advertised.

path attribute entries

Number of distinct path attributes stored in BGP's internal path attributes table. If BGP receives two routes for different prefixes but with identical path attributes, BGP will create only one entry in its internal path attribute table and share it between the two routes to conserve memory.

Local-RIB version

Number that is increased by one each time a route in that RIB is added, removed or modified.

FIB version

Number that is increased by one each time BGP updates the routes in the IP routing table based on changes in the local RIB. The FIB version matches the local-RIB version when BGP has finished updating the routes in the IP route table. The FIB version is less than the local-RIB version when BGP is still in the process of updating the IP routing table.

Prefix

Prefix for the routing table entry

Peer

Peer from which route was learned

Next hop IP address

IP address of the next router that is used when a packet is forwarded to the destination network

MED

Multiexit discriminator for the route

LocPrf

Local preference for the route

Weight

Weight of the route

Origin

Origin of the route

AS path

AS path through which this route has been advertised

Communities

Community number associated with the route

Stale

Routes that have gone stale due to peer restart

unicast/multicast routes selected for route table installation

Number of unicast routes in the BGP routing table that have been inserted into the IP routing table that are also available for use in the multicast view of the IP routing table

unicast/multicast tunnel-usable routes selected for route table installation

Number of unicast and multicast routes in the BGP routing table that have been inserted into the IP routing table that are also available for use in the IP tunnel routing table

tunnel-only routes selected for tunnel-route table installation

Number of routes in the BGP routing table that have been inserted into the IP tunnel routing table

path attribute entries

Number of distinct path attributes stored in BGP's internal path attributes table. If BGP receives two routes for different prefixes but with identical path attributes, BGP will create only one entry in its internal path attribute table and share it between the two routes to conserve memory.

Statistics baseline set

Timestamp indicating when the statistics baseline was last set

Route-map

Indicates whether network-route filtering is enabled

Backdoor

Indicates whether an IGP backdoor route is favored over an EBGP route

CalPrf

Calculated preference

Related Documentation