From owner-freebsd-net@freebsd.org  Sat Sep 15 06:06:18 2018
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Date: Sat, 15 Sep 2018 08:06:15 +0200
From: Kurt Jaeger <pi@freebsd.org>
To: Eric van Gyzen <eric@vangyzen.net>
Cc: freebsd-current@freebsd.org, freebsd-net@freebsd.org
Subject: Re: Bad DHCP Checksums over VLANs
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Hi!

> The server NIC is common (I211), so maybe it's easy to reproduce.  I'll 
> help as much as I can, of course.

Can you disable all the options of the NIC ?

ifconfig igb0 -rxcsum -txcsum -wol -tso4 -vlanmtu -vlanhwtag -vlanhwcsum -vlanhwtso

Try to disable everything that can be disabled, e.g. LRO etc.

-- 
pi@FreeBSD.org         +49 171 3101372              2 years to go !