April 15, 2010

BGP Next-Hop-Self Attribute

The BGP Next Hop Attribute is useful when passing routes received from an eBGP speaker and advertised to an iBGP speaker within the same Autonomous System. By default when a route is advertised to an eBGP outside of the AS, the router will make sure that the next hop attribute reflects its IP address… now imagine a route is advertised to an iBGP speaker and sourced into the BGP AS group. ... Read more

March 4, 2010

quaggOS 0.1a1 released - OSPF/BGP routing solution

Hi, I am pleased to announce that quaggOS in alpha version has been released. quaggOS is a live linux distribution I created which turns a server/pc into a full BGP/OSPF router. This is achieved by using the Quagga routing solution application. For more information, visit http://quaggOS.org To download and test the alpha release, click here

September 20, 2009

Filter networks with BGP

There are 3 easy ways to filter/restrict certain networks to be announced through BGP to a remote/adjacent AS (Autonomous System). Those 3 simple ways include: prefix-list | Extended Access-list + Route-map | Extended Access-list + Distribute-list To Note: before we go on, I need to specify that creating an extended access list to be in use with BGP (route-map, distribute-list) is almost as similar as creating a prefix-list… Having said that, we are therefore no longer matching source and destination address but merely address prefix and netmask with the access list. ... Read more

September 18, 2009

iBGP route reflectors

It is by default that all BGP peers within the same autonomous systems must peer with each other to form a full mesh in order for each peer to be able to advertise routes to its adjacent peer. “Disclaimer: BGP confederacies will not be tackled in this post” **For example ** if routerB learns a new route from routerA, it wouldn’t be able to advertise the learned route to routerC and routerC would only be able to learn the route from routerA. ... Read more