On Mon, 7 Sept 2026 at 17:48, Saku Ytti <saku@ytti.fi> wrote:
On Mon, 7 Sept 2026 at 17:13, Lukas Tribus via NANOG <nanog@lists.nanog.org> wrote:
We loose interface information in traceroutes if use loopbacks for ICMP errors. I'd immagine people have different opinions about whether this is a problem or not.
There is RFC about ICMP-EO to attach this metadata, including device name as well as actual port (not the ECMP logical but physical). This ICMP-EO would allow you to reliably troubleshoot which port is actually lossy, as well as it would allow you to automatically discover what ports to set in your QoS measurement, to capture all paths
Thanks, that would be RFC 5837, I did not know about that one. Looks like Arista has joined Juniper in implementing this [1] and Linux has it since 6.19. [1] https://arista.my.site.com/AristaCommunity/s/question/0D5Uw000001yvSvKAI/eos...