nanog mailing list archives

Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging


From: Joshua Miller <contemno () gmail com>
Date: Mon, 3 Apr 2023 01:35:43 -0400

Is the BGP route getting installed into the rib?




On Mon, Apr 3, 2023, 01:24 Mike Hammett <nanog () ics-il net> wrote:

We have a Nexus 3064 that is setup with partial BGP tables and is routing
based on that.


I've done a show ip bgp for an IP of interest and it has an expected next
hop IP. I show ip arp on that next hop IP and it has the expected interface.



However, sFlows show the packets leaving on a different interface, the one
that would carry the default route for routes not otherwise known.


If the next hop IP is expected and the ARP of that next hop IP is
expected, why are packets leaving out an unexpected interface?



-----
Mike Hammett
Intelligent Computing Solutions
http://www.ics-il.com

Midwest-IX
http://www.midwest-ix.com



Current thread: