I have AS and own PI prefixes. I have 2 BGP routers in different locations (A and B). Router A announces some prefixes and B announces another prefixes. Between routers A and B is iBGP session (direct leased link connecting those two routers).
Now I have to launch third location C with another BGP router within same AS.
Do I have to make full mesh iBGP connections between routers A,B and C (I mean dedicated direct links) or may I use some other techniques like tunnels, or whatever, to establish iBGP connections?
As long as you have a route at the existing routers which enables you to reach the third iBGP neighbor, and that new iBGP neighbor has a route back to your 2 existing routers, you can peer up with that new (third) router.
No direct connection, or dedicated facility is needed to do this. All three routers need to have routes / reachability with each other, that's all. And yes, full mesh should be used - or - route reflection.
I have 2 locations (2 routers BGP using the same AS): A and B. On each site I have separate BGP upstream links to at least 2 peers (on each site), so in fact, those routers are using the same AS but are announcing different prefixes. I just have done my internal assignement: prefix X is used in location A, and prefix Y in B.
It's done this way to provide my customers Internet using my PI adresses on each location. Now, because routers A and B use the same AS, so, I need iBGP session to reach prefix X (announced by A) from B, and vice versa. My AS is'nt big enough to make some internal traffic policy so I just need some way to reach my prefixes between sites. Unfortunetly, I have very poor direct leased link between those sites.
I have to change it, and I am thinking of alternative solutins, for example:
- make iBGP session between A and B using GRE over Internet (if possible)
- use allowas-in to receive prefix X on router B through foreign peers (normaly BGP blocks prefikses originated from own AS).
I don't know if my english is precise enough but I tried to explain situation as good as I can. The question is: "what solution is better?"
Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.