- We didn’t have Internet BGP routing table in any of our router. Hurricane Electric advertised it to us but the inbound Route-Map “HE” policy that blocks the Bogons missed the permit at the end and therefore the default implicit deny at the end of the Route-Map blocked all the advertised BGP routes. By adding rule 20 { action permit } at the end of that policy we received the full Internet BGP routing table.
- The iBGP between the routers missed the command “nexthop-self” and therefore the routes advertised by router s to each other were not accessible because the origin was the other provider which is not accessible from the other one.
- Cogent didn’t advertise the full BGP table to us and we contacted their customer service and asked them to do so. They asked if we want to remove the default gateway on their side. More clarification is needed about this. Currently we have two BGP sessions with two IPs in Cogent: One for receiving the routes and the other for advertising our subnets. One is with the IP on Cogent side the point-point link that we have with them and the other one is not. They said that we can change the configuration and use only one IP for both purposes. We decided to do this after router updates.
- The policy as-path-list named “ACME” was missing from IPv6 BGP with HE in Router1. This policy is necessary in order to prevent transiting traffic that is not originated in our network. Basically it prevents advertising any path that already has an AS number on its advertisement.
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