BGP connection to Blackhole server with Cogent

RouterOS Forwarding Protocols
1

HI All,

After great presentation made by Lorenzo Busatti (Grifonline S.r.l., Italy) I have decided to establish BGP peer with blackhole server with my upstream provider - Cogen.

I made configuration based on their information and now peer is connecting only for milliseconds.

07:27:03 route,bgp,info TCP connection established 
07:27:03 route,bgp,info     RemoteAddress=130.117.20.1 
07:27:03 route,bgp,info Connection terminated 
07:27:03 route,bgp,info     RemoteAddress=130.117.20.1

My configuration loos like:

.routing bgp peer
add in-filter=cogent-blackhole-in multihop=yes name=Cogent-BlackHole out-filter=cogent-blackhole-out remote-address=130.117.20.1 remote-as=174 tcp-md5-key=<my-md5-key> ttl=default update-source=<interface-facing-cogent-or-ip-that-was-sent-to-Cogent>

I was playing with that configuration few hours, without luck.
When I remove md5 key from configuration - Cogen will not even respond for my BGP session.
So in my opinion there is fault on their side - or maybe I’m missing something on my side.
That is first configuration with multihop option on my side.

I’m happily using 40 other peers connection - without such issues.

2

This sounds like your update-source isn’t sending the IP that they’re expecting your requests to come from.
Double check that whatever IP you set up as your side of the peering, that’s the one your router is using to communicate with the blackhole server.