BGP Configuration

Outline

This challenge involves the configuration of BGP. The objectives of this challenge are to:

• Define BGP routing.
• Define networks to broadcast into.
• Define the default network.
• Define the timers. The main timers in BGP are keepalive and holddown.

The definitions for the timers are:

• Keepalive. This shows to other devices that the device is still alive.
• Holddown timers. This is the time that the device will wait between hearing Keepalive (or Update) messages from a neighbor. The default is 180 seconds (three times the keepalive), but can be reconfigured.

Commands

> enable

# config t

(config)# hostname edinburgh

(config)# router bgp 123

(config-router)# network 10.1.0.0

(config-router)# network 10.2.0.0

(config-router)# network 10.3.0.0

(config-router)# timers bgp 10 14

(config-router)# exit

(config)# ip default-network 10.1.1.0

Example

> enable

# config t

(config)# hostname edinburgh

(config)# router ?

bgp Border Gateway Protocol (BGP)

egp Exterior Gateway Protocol (EGP)

eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)

igrp Interior Gateway Routing Protocol (IGRP)

isis ISO IS-IS

iso-igrp IGRP for OSI networks

mobile Mobile routes

odr On Demand stub Routes

ospf Open Shortest Path First (OSPF)

rip Routing Information Protocol (RIP)

static Static routes

(config)# router bgp ?

<1-65535> Autonomous system number

(config)# router bgp 123 ?

<cr>

(config)# router bgp 123

(config-router)# ?

Router configuration commands:

address-family Enter Address Family command mode

aggregate-address Configure BGP aggregate entries

auto-summary Enable automatic network number summarization

bgp BGP specific commands

default Set a command to its defaults

default-information Control distribution of default information

default-metric Set metric of redistributed routes

distance Define an administrative distance

distribute-list Filter networks in routing updates

exit Exit from routing protocol configuration mode

help Description of the interactive help system

maximum-paths Forward packets over multiple paths

neighbor Specify a neighbor router

network Specify a network to announce via BGP

no Negate a command or set its defaults

redistribute Redistribute information from another routing protocol

synchronization Perform IGP synchronization

table-map Map external entry attributes into routing table

timers Adjust routing timers

(config-router)# network ?

A.B.C.D Network number

(config-router)# network 10.1.0.0 ?

backdoor Specify a BGP backdoor route

mask Network mask

route-map Route-map to modify the attributes

<cr>

(config-router)# network 10.1.0.0

(config-router)# network 10.2.0.0

(config-router)# network 10.3.0.0

(config-router)# timers ?

bgp BGP timers

(config-router)# timers bgp ?

<0-4294967295> Keepalive interval

(config-router)# timers bgp 10 ?

<0-4294967295> Holdtime

(config-router)# timers bgp 10 14 ?

<cr>

(config-router)# timers bgp 10 14

(config-router)# exit

(config)# ip default-network ?

A.B.C.D IP address of default network

(config)# ip default-network 10.1.1.0 ?

<cr>

(config)# ip default-network 10.1.1.0