nanog mailing list archives
Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging
From: Mike Hammett <nanog () ics-il net>
Date: Mon, 3 Apr 2023 07:48:17 -0500 (CDT)
What started this investigation was a client complained of traffic coming from another upstream instead of our direct connection. ----- Mike Hammett Intelligent Computing Solutions http://www.ics-il.com Midwest-IX http://www.midwest-ix.com ----- Original Message ----- From: "Mike Hammett" <nanog () ics-il net> To: "NANOG" <nanog () nanog org> Sent: Monday, April 3, 2023 12:21:29 AM Subject: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging 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:
- RE: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging, (continued)
- RE: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Matthew Huff (Apr 03)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Mike Hammett (Apr 03)
- RE: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Matthew Huff (Apr 03)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Mike Hammett (Apr 03)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Mike Hammett (Apr 03)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging David Bass (Apr 03)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Mike Hammett (Apr 04)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging David Bass (Apr 04)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Mike Hammett (Apr 04)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Nick Olsen (Apr 04)
- Re: Cisco Nexus 3k Route Selection\Packet Forwarding Debugging Joelja Bogus (Apr 16)