OK, this is even crazier, and now I may never find it. After updating and restarting the router this issue happened, but I found out I forgot one of the prefix lists to a peer, so thought OK, let’s be safe and just reload the BGP configs I had stored to be safe. After doing that reload, the local route vanished as mentioned before, and now everything is showing clean:
#sho ip route 206.126.237.0 Routing entry for 206.126.237.0/32, 1 known subnets Attached (1 connections) L 206.126.237.136 is directly connected, Vlan99 I guess the change caused it to update the fib, and it seems to be working right. I ran the command as you requested Fabio, but of course now it looks fine.. #show ip cef 206.126.236.37 detail 206.126.236.37/32, epoch 8, flags attached Adj source: IP adj out of Vlan99, addr 206.126.236.37 4C4BADE0 Dependent covered prefix type adjfib, cover 206.126.236.0/22 2 RR sources [heavily shared] attached to Vlan99 Would love to know what happened, but at the moment guessing I’d be chasing my tail.. --- Howard Leadmon PBW Communications, LLC http://www.pbwcomm.com From: Fabio Mendes [mailto:[email protected]] Sent: Tuesday, November 22, 2016 7:59 PM To: Howard Leadmon <[email protected]> Cc: Cisco Network Service Providers <[email protected]> Subject: Re: [c-nsp] Strange Routing.. What does a 'show ip cef detail' return for those? On Tue, Nov 22, 2016 at 7:15 PM, Howard Leadmon <[email protected] <mailto:[email protected]> > wrote: OK, and in my terrible lack of sleep maybe I am missing something that I shouldn't be, but here is the issue.. I have a 7606 with RSP720's running IOS 15.3(3)S6 at this time. Across the Ashburn exchange they use the IP block of 206.126.236.0/22 <http://206.126.236.0/22> for peering. If I look at the router and ask it for the routing for this block I see: #sho ip route 206.126.236.0 Routing entry for 206.126.236.0/22 <http://206.126.236.0/22> , supernet Known via "connected", distance 0, metric 0 (connected, via interface) Routing Descriptor Blocks: * directly connected, via Vlan99 Route metric is 0, traffic share count is 1 My IP in use on the exchange is 206.126.237.136 So if I run a show route on a few peers we connect with, I would expect it to fall inside the above supernet, and if they are in .236, .238, or .239 they do, but not if they are part of .237. As an example: #sho ip route 206.126.236.37 Routing entry for 206.126.236.0/22 <http://206.126.236.0/22> , supernet Known via "connected", distance 0, metric 0 (connected, via interface) Routing Descriptor Blocks: * directly connected, via Vlan99 .236 is good.. #sho ip route 206.126.237.37 % Subnet not in table .237 is bad.. #sho ip route 206.126.238.37 Routing entry for 206.126.236.0/22 <http://206.126.236.0/22> , supernet Known via "connected", distance 0, metric 0 (connected, via interface) Routing Descriptor Blocks: * directly connected, via Vlan99 .238 is good, as well at .239.. If I look at the routes I see the router seems to be injecting a local /32 which doesn't make a lot of sense to me either: #sho ip route 206.126.237.0 Routing entry for 206.126.237.0/32 <http://206.126.237.0/32> , 1 known subnets Attached (1 connections) L 206.126.237.136 is directly connected, Vlan99 This is causing connection issues for some of the peers for sure, and a static route for the /24 will add it to the routing table, I am at a total lost as to why it's not already present with the /22 in the table, and with the fact the interface to the IX shows with a mask of 255.255.252.0. All of my IPv6 is great, just this one issue with IPv4 driving me batty. Any suggestions or advice most welcome.. --- Howard Leadmon PBW Communications, LLC <http://www.pbwcomm.com> http://www.pbwcomm.com _______________________________________________ cisco-nsp mailing list [email protected] <mailto:[email protected]> https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
