Only one issue, if you are going to do peering using loopback, you'll need to use the "neighbor x.x.x.x ebgp-multihop 2" command for the neighbor ship to build up, plus of course "neighbor x.x.x.x update-source loopback0".
Another thing to put in mind in any eBGP peering is the route filtering, you should decide whether you need to receive all the routes that this neighbor sends or not.
Thx,Mohammed. I meant to ask if there are any service implications to be considered when implementing multihop peering.
Reason being that there are pt-pt links between the Rtrs but the client has decided to use multihop rather than peer directly with the physical interfaces. I am trying to understand why this was implemented this way.
One of the reason could be the client router that is directly connected to your BGP router via point-to-point link is not capable of running BGP, the BGP router might be behind it (one hop away). One of the reason this could happen is the BGP router is not able to connect to point-to-point link as it does not support the media or not enough slot to put a module or interface for the point-to-point link, I see a lot of these happens.
Don't forget to put a password for all eBGP multihop implementation.
Most probably the client is trying to achieve load sharing and thats why he is going to peer with loopbacks, and the answer is no there is no any implications for using multihop eBGP, all it does is increase the TTL value of the sent BGP messages.
I checked a couple of these external routers and they are all connected over a Pt-Pt FR Ckt. Initially I thought that the far-end routers were behind somewhere in the providers cloud, but they they are connected via a T1/FR.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.