Re: Response error to fragmented ICMP echo request

From: Vladimir Oltean
Date: Tue Mar 07 2023 - 08:20:06 EST


On Tue, Mar 07, 2023 at 12:56:17PM +0000, Song, Xiongwei wrote:
> > Frames 3 and 4 are sent with DEI=1 and are dropped, frames 1 and 2 are
> > sent with DEI=0 and are not dropped. I'm not sure if varying the DEI
> > field is part of the intentions of the test? Is there any RFC which says
> > that IP fragments over VLAN should use DEI=1, or some other reason?
>
> I didn't notice that. Let me check the test why set DEI=1.

Ok. It would be good to have an answer to this, because one of the
assumptions of that patch was that whomever sets DEI=1 doesn't get to
complain that their packets are *actually* dropped :)

FWIW, if you do need to set up a reservation for traffic received on a
port, section 8.6.3.3.15 Buffer reservation watermarks (page 817) should
help with this:
https://www.nxp.com/docs/en/user-guide/LLDPUG_RevL5.15.71-2.2.0.pdf