Verifying BGP Configuration

Topics:

•	Viewing BGP Routes

•	Configuring BGP Logging

Viewing BGP Routes

The figure below shows a basic BGP topology where a SonicWALL security appliance is configured for BGP to connect to two routers on two different ASs.

Figure 53. BGP topology

The routes in the FIB for this network can be viewed either in the SonicOS GUI or by using the CLI.

Topics:

•	Viewing FIB routes in the GUI

•	Viewing FIB Routes in the CLI

•	Viewing RIB Routes in the CLI

Viewing FIB routes in the GUI

A summary of the BGP configuration can be viewed on the SonicOS GUI through the Network > Routing page by clicking the BGP Status button, located at the top of the page next to the Routing Mode drop-down menu. The BGP Status window displays the output of the show ip bgp summary and show ip bgp neighbor commands.

The BGP routes in the FIB can also be viewed on the SonicOS GUI in the Routing Policies table on the Network > Routing page.

Viewing FIB Routes in the CLI

To view the FIB routes in the CLI, perform the following commands:

SonicWALL> configure

(config[SonicWALL])> route ars-nsm

 

ZebOS version 7.7.0 IPIRouter 7/2009

ARS NSM>show ip route

Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP

O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area

* - candidate default

 

B 7.6.7.0/24 [20/0] via 10.50.165.228, X1, 05:08:31

B 199.199.0/16 [20/0] via 10.50.165.237, X1, 05:08:31

C 10.50.165.192/26 is directly connected, X1

C 127.0.0.0/8 is directly connected, lo0

C 12.34.5.0/24 is directly connected, X0

Viewing RIB Routes in the CLI

To view the RIB routes in the CLI, enter the show ip bgp command:

ARS BGP>show ip bgp

BGP table version is 98, local router ID is 10.50.165.233

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, l - labeled

S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 7.6.7.0/24 10.50.165.228 0 0 7675 i

*> 12.34.5.0/24 0.0.0.0 100 32768 i

*> 199.199.0.0/16 10.50.165.228 0 0 7675 9999 i

Total number of prefixes 3

NOTE: The last route is the path to AS9999 that was learned through AS7675.

Configuring BGP Logging

SonicWALL BGP offers a comprehensive selection of debug commands to display log events related to BGP traffic. BGP logging can be configured on the CLI by using the debug bgp command followed by of the following keywords:

 

Table 110. BGP debug keywords

BGP Debug Keywords	Description
all	Enables all BGP debugging.
dampening	Enables debugging for BGP dampening.
events	Enables debugging for BGP events.
filters	Enables debugging for BGP filters.
fsm	Enables debugging for BGP Finite State Machine (FSM).
keepalives	Enables debugging for BGP keepalives.
nht	Enables debugging for NHT messages.
nsm	Enables debugging for NSM messages.
updates	Enables debugging for inbound/outbound BGP updates.

To disable BGP debugging, enter the “no” form of the command. For example, to disable event debugging, type the no debug events command.

BGP log messages can also be viewed on the SonicOS GUI on the Log > View page. BGP messages are displayed as part of the Advanced Routing category of log messages.

The above message indicates that an update to the outgoing RIB was denied because the router from which the update was received was not directly connected to the appliance.

To allow for BGP peers that are not directly connected, use the ebgp-multihop keyword with the neighbor command. For example:

neighbor 10.50.165.228 ebgp-multihop