Cisco CCNP / BSCI Tutorial: The BGP Attribute NEXT_HOP 30745

When you're learning for the BSCI examination on the way to gaining your CCNP certification, you have got to master the use of BGP attributes. These capabilities allow you to change the road or paths that BGP use to reach certain destination when multiple paths to that destination exist.

In this free BGP tutorial, we are likely to have a look in the NEXT_HOP characteristic. This dazzling alternative to linklicious link has a few stirring warnings for why to recognize it. You may well be considering "hey, how complicated may this credit be?" It is not to difficult at all, but this being Cisco, there's got to be at least one unusual aspect about it, right?

The NEXT_HOP attribute is easy enough - this attribute indicates the next-hop IP address that should be taken to reach a destination. Be taught new info about linklicious by going to our rousing use with. Within the following example, R1 is a link hub and R2 and R3 are spokes. All three routers are in BGP AS 100, with R1 having a connection with both R2 and R3. There is no BGP peering between R3 and R2.

R3 is advertising the community /24 via BGP, and the importance of the next-hop characteristic on R1 is the IP address on R3 that's found in the peer relationship, If you believe anything, you will probably want to study about review.

The issue with the credit will come in when the route is advertised to BGP peers. If R3 were in a different AS from R1 and R2, R1 would then advertise the route to R2 with the attribute set to When a BGP speaker advertises a route to iBGP friends that has been actually learned from an eBGP expert, the next-hop value is maintained.

Here, all three routers come in AS 100. Dig up more on linklicious senuke by visiting our forceful article directory. What'll the attribute be set to when R1 advertises the path to its iBGP friend R2?

R2#show ip address bgp

< no production >

There will be no next-hop credit for the route on R2, since the route will not look on R2. Automatically, a BGP speaker won't advertise a to iBGP neighbors if the route was first learned from another iBGP neighbor.

Fortuitously for all of us, there are numerous ways around this rule. The most frequent is the utilization of route reflectors, and we'll look at RRs in a future free BGP tutorial..