bgp issue

ttuncaral · ‎05-11-2005

I have a problem configuring bgp on our system.

configuration like this:

isp1-Rtra-eth-Rtrb-atmpvc-Rtrc-eth-Rtrd-isp2

there is a network 10.1.1.0/24 which is connected to Rtra. this network must be announced primarily to isp2 but in case of connection loss to isp2 this network must be advertised thru isp1. There are several other networks which must be advertised thru these ISPs but only this network must have optional redundancy in the AS.

I tried to solve the problem by defining all of these in the same autonomous system but I met some connectivity problems. I must also note that there is a huge network behind Rtrb and Rtrc and these two also run EIGRP.

Shall I define a different internal BGP AS between RtrB and Rtrc and split the main AS into two seperate ASs or go with the same AS for all Rtrs?

I mainly need some hints and approach to my problem not the configuration commands now.

Thanks for any help

Georg Pauwen · ‎05-11-2005

Hello,

do RtrB and RtrC also run BGP ? On RtrA, you could define a route-map matching network 10.1.1.0/24 and assign a lower weight or local preference for the connection to ISP1 than to RtrB.

HTH,

GP

ttuncaral · ‎05-11-2005

First I tried to put all the routers into same AS. Use RR on Rtrb and Rtrc. RtrA and Rtrd is connected to outside world and just one connected network(10.1.1.0/24) of Rtra must be announced thru Rtrd. When Rtrd lost its connection to Isp2 then AS must announce it to Isp1 which is directly connected to Rtra.

I would like to ask my problem in this way, shall I solve this problem routing BGP in the same AS or use different ASs and split the outside world into two segments? I mean, is there any difference between this two approach? I can choose many ways(e.g IGP between Rtrb and Rtrc or private AS) but which would be more efficient?

Thanks for your help.

ttuncaral · ‎05-12-2005

I made a search on previous conversations and found a document titled "load sharing with BGP in single...." in your replies. This document helped me to understand my situation and now I am ready to move one step forward wisely. Thanks for your help to me and to the others.