[j-nsp] [c-nsp] Stange issue on 100 Gbs interconnection Juniper - Cisco

[Saku Ytti]

On Sun, 11 Feb 2024 at 17:52, james list <jameslist72 at gmail.com> wrote:

> - why physical interface flaps in DC1 if it is related to lacp ?

16:39:35.813 Juniper reports LACP timeout (so problem started at
16:39:32, (was traffic passing at 32, 33, 34 seconds?))
16:39:36.xxx Cisco reports interface down, long after problem has
already started

Why Cisco reports physical interface down, I'm not sure. But clearly
the problem was already happening before interface down, and first log
entry is LACP timeout, which occurs 3s after the problem starts.
Perhaps Juniper asserts for some reason RFI? Perhaps Cisco resets the
physical interface once removed from LACP?

> - why the same setup in DC2 do not report issues ?

If this is is LACP related software issue, could be difference not
identified. You need to gather more information, like how does ping
look throughout this event, particularly before syslog entries. And if
ping still works up-until syslog, you almost certainly have software
issue with LACP inject at Cisco, or more likely LACP punt at Juniper.

-- 
  ++ytti