Verifying a BGP Configuration

To verify a BGP configuration, perform these tasks:

Purpose

Verify that BGP is running on configured interfaces and that the BGP session is active for each neighbor address.

Action

From the CLI, enter the show bgp neighbor command.

Peer: 10.255.245.12+179 AS 35  Local: 10.255.245.13+2884 AS 35   
  Type: Internal    State: Established  (route reflector client)Flags: Sync
  Last State: OpenConfirm   Last Event: RecvKeepAlive
  Last Error: None
  Options: Preference LocalAddress HoldTime Cluster AddressFamily Rib-group Refresh
  Address families configured: inet-vpn-unicast inet-labeled-unicast
  Local Address: 10.255.245.13 Holdtime: 90 Preference: 170
  Flags for NLRI inet-vpn-unicast: AggregateLabel	
  Flags for NLRI inet-labeled-unicast: AggregateLabel	
  Number of flaps: 0
  Peer ID: 10.255.245.12    Local ID: 10.255.245.13    Active Holdtime: 90
  Keepalive Interval: 30
  NLRI advertised by peer: inet-vpn-unicast inet-labeled-unicast
  NLRI for this session: inet-vpn-unicast inet-labeled-unicast
  Peer supports Refresh capability (2)
Restart time configured on the peer: 300 
  Stale routes from peer are kept for: 60 
  Restart time requested by this peer: 300 
  NLRI that peer supports restart for: inet-unicast inet6-unicast 
  NLRI that restart is negotiated for: inet-unicast inet6-unicast 
  NLRI of received end-of-rib markers: inet-unicast inet6-unicast 
  NLRI of all end-of-rib markers sent: inet-unicast inet6-unicast 
  Table inet.0 Bit: 10000
    RIB State: restart is complete 
    Send state: in sync
    Active prefixes: 4
    Received prefixes: 6
    Suppressed due to damping: 0
  Table inet6.0 Bit: 20000
    RIB State: restart is complete 
    Send state: in sync
    Active prefixes: 0
    Received prefixes: 2
    Suppressed due to damping: 0
  Last traffic (seconds): Received 3    Sent 3    Checked 3   
  Input messages:  Total 9      Updates 6       Refreshes 0     Octets 403
  Output messages: Total 7      Updates 3       Refreshes 0     Octets 365
  Output Queue[0]: 0
  Output Queue[1]: 0
  Trace options: detail packets
  Trace file: /var/log/bgpgr size 131072 files 10

What it Means

The output shows a list of the BGP neighbors with detailed session information. Verify the following information:

• Each configured peering neighbor is listed.
• For State, each BGP session is Established.
• For Type, each peer is configured as the correct type (either internal or external).
• For AS, the AS number of the BGP neighbor is correct.

For more information about show bgp neighbor, see the JUNOS Routing Protocols and Policies Command Reference.

Purpose

Verify that the BGP groups are configured correctly.

Action

From the CLI, enter the show bgp group command.

Group Type: Internal    AS: 10045       Local AS: 10045
  Name: pe-to-asbr2                                     Flags: Export Eval
  Export: [ match-all ] 
  Total peers: 1        Established: 1
  10.0.0.4+179
  bgp.l3vpn.0: 1/1/0
  vpn-green.inet.0: 1/1/0

Groups: 1   Peers: 1    External: 0    Internal: 1    Down peers: 0   Flaps: 0
Table          Tot Paths  Act Paths Suppressed    History Damp State    Pending
bgp.l3vpn.0            1          1          0          0          0          0

What it Means

The output shows a list of the BGP groups with detailed group information. Verify the following information:

• Each configured group is listed.
• For AS, each group's remote AS is configured correctly.
• For Local AS, each group's local AS is configured correctly.
• For Group Type, each group has the correct type (either internal or external).
• For Total peers, the expected number of peers within the group is shown.
• For Established, the expected number of peers within the group have BGP sessions in the Established state.
• The IP addresses of all the peers within the group are present.

For more information about show bgp group, see the JUNOS Routing Protocols and Policies Command Reference.

Purpose

Verify that the BGP configuration is correct.

Action

From the CLI, enter the show bgp summary command.

Groups: 1 Peers: 3 Down peers: 0
Table          Tot Paths  Act Paths Suppressed    History Damp State    Pending
inet.0                 6          4          0          0          0          0
Peer               AS      InPkt     OutPkt    OutQ   Flaps Last Up/Dwn State|#Active/Received/Damped...
10.0.0.2        65002      88675      88652       0       2       42:38 2/4/0                0/0/0
10.0.0.3        65002      54528      54532       0       1     2w4d22h 0/0/0                0/0/0
10.0.0.4        65002      51597      51584       0       0     2w3d22h 2/2/0                0/0/0

What it Means

The output shows a summary of BGP session information. Verify the following information:

• For Groups, the total number of configured groups is shown.
• For Peers, the total number of BGP peers is shown.
• For Down Peers, the total number of unestablished peers is 0. If this value is not zero, one or more peering sessions are not yet established.
• Under Peer, the IP address for each configured peer is shown.
• Under AS, the peer AS for each configured peer is correct.
• Under Up/Dwn State, the BGP state reflects the number of paths received from the neighbor, the number of these paths that have been accepted, and the number of routes being damped (such as 0/0/0). If the field is Active, it indicates a problem in the establishment of the BGP session.

For more information about show bgp summary, see the JUNOS Routing Protocols and Policies Command Reference.

Purpose

By using the ping tool on each peer address in the network, verify that all peers in the network are reachable from each Services Router.

Action

For each Services Router in the BGP network:

1. In the J-Web interface, select Diagnose>Ping Host.
2. In the Remote Host box, type the name of a host for which you want to verify reachability from the Services Router.
3. Click Start. Output appears on a separate page.

PING 10.10.10.10 : 56 data bytes
64 bytes from 10.10.10.10: icmp_seq=0 ttl=255 time=0.382 ms
64 bytes from 10.10.10.10: icmp_seq=1 ttl=255 time=0.266 ms

What it Means

If a host is active, it generates an ICMP response. If this response is received, the round-trip time is listed in the time field. For more information about the ping output, see the J-series Services Router Administration Guide.

For more information about using the J-Web interface to ping a host, see the J-series Services Router Administration Guide.

For information about the ping command, see the J-series Services Router Administration Guide or the JUNOS System Basics and Services Command Reference.