BGP next hop self explained

BGP next hop is a mandatory attribute of BPG which provide information of the next hop for the advertised subnet. iBGP doesn’t change the next hop of advertised subnets. BGP next hop self can help in changing the next hop of advertised subnets in IBGP. Let’s understand the why we need BGP next hop self. … Read more

BGP Origin Code Attribute

There are three BGP origin code attribute which are used in path selection. The bgp table can be checked using show ip bgp command We will use the same topology which we have used in our basic BGP configuration post. To learn about the origin codes we will do following: i origin code: A route … Read more

Basic BGP configuration

In this post we will learn basic BGP configuration on Cisco IOS router, we will advertise network to the EBGP peers and test connectivity. The post is in continuation of the BGP concepts discussed in previous post. We will use below topology for this basic BGP configuration example. We have two router Router3, Router4. ASN3 … Read more

BGP Border Gateway Protocol Concepts

BGP (border gateway protocol) is a routing protocol used in internet. Entire public subnets are given to various ISPs and allocated with an AS (autonomous system) number. Now these various subnets are interconnected and the job to find out which IP subnet is where and how to reach that subnet is done by BGP. BGP … Read more

Cisco Router Password recovery

There can be certain situation where we may loose access to a Cisco CSR router and due to that we would not be able to login to the device. In such situations we can do password recovery of Cisco router to regain access to the device, by password recovery we will not loose any configuration … Read more