CCNA

Jan 22 2009

BGP – Prefix aggregation using a static route

My previous post on BGP prefix aggregation used the bgp “aggregate-address” command.  Another way to generate an aggregate is by using a static route.

Consider the toplology below.

bgp-small2Watch the video below to see how to configure a BGP aggregate using a static route.  Alternatively down the video here and watch it on your iPod.

The Flash plugin is required to view this object.

The commands used in the above video are listed below.

R1
!
interface FastEthernet1/0
ip address 10.0.0.1 255.255.255.252
!
router bgp 1
neighbor 10.0.0.2 remote-as 2
no auto-summary

R2
!
interface Loopback0
ip address 192.168.0.1 255.255.255.0
!
interface Loopback1
ip address 192.168.1.1 255.255.255.0
!
interface Loopback2
ip address 192.168.2.1 255.255.255.0
!
interface Loopback3
ip address 192.168.3.1 255.255.255.0
!
interface FastEthernet1/0
ip address 10.0.0.2 255.255.255.252
!
router bgp 2
no synchronization
bgp log-neighbor-changes
network 192.168.0.0
network 192.168.1.0
network 192.168.2.0
network 192.168.3.0
redistribute static
neighbor 10.0.0.1 remote-as 1
no auto-summary

By Zarar • BGP, CCIE, CCIE SP, CCIP, CCNA, CCNP, iPod • 0 • Tags: , , , , ,

Dec 28 2008

New Cisco Certifications Logo

I came across this link recently.  It suggests that Cisco Certification Logos are changing.

Follow the link to see the new logos.

By zismail • CCIE, CCIE SP, CCIP, CCNA, CCNP • 0

Dec 26 2008

BGP Route Aggregation

There are times when it is required to aggregate a set of prefixes.  There are a number of reasons why you would want to do this such as, your peering transit edge may not accept certain size prefixes, you may want to reduce the size of the routing table in some part of your network etc etc.

Consider the topology below:-

bgp-aggregate

Watch how to use the aggregate command below, or alternatively download the video and watch it on your iPod.

The Flash plugin is required to view this object.

The commands used in the above setup are as below.

R1

interface FastEthernet1/0
description "Interface connected to R2"
ip address 10.0.0.1 255.255.255.252
!
router bgp 1
no synchronization
bgp log-neighbor-changes
neighbor 10.0.0.2 remote-as 2
no auto-summary

R2

interface FastEthernet1/0
description "Interface connected to R1"
ip address 10.0.0.2 255.255.255.252
!
interface Loopback0
ip address 192.168.0.1 255.255.255.0
!
interface Loopback1
ip address 192.168.1.1 255.255.255.0
!
interface Loopback2
ip address 192.168.2.1 255.255.255.0
!
interface Loopback3
ip address 192.168.3.1 255.255.255.0
!
router bgp 2
no synchronization
bgp log-neighbor-changes
network 192.168.0.0
network 192.168.1.0
network 192.168.2.0
network 192.168.3.0
aggregate-address 192.168.0.0 255.255.252.0 suppress-map SUPPRESS-2-ONLY
neighbor 10.0.0.1 remote-as 1
no auto-summary
!
access-list 1 permit 192.168.2.0 0.0.0.255
!
route-map SUPPRESS-2-ONLY permit 10
match ip address 1

By zismail • BGP, CCIE, CCIE SP, CCIP, CCNA, CCNP, iPod • 0 • Tags: , , , , ,