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Date: Thu, 11 Jan 2007 12:44:03 +0100
From: Bernd Walter <ticso@cicely12.cicely.de>
To: Pietro Cerutti <pietro.cerutti@gmail.com>
Message-ID: <20070111114402.GX80390@cicely12.cicely.de>
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Cc: freebsd-hackers@freebsd.org,
	FreeBSD Questions <freebsd-questions@freebsd.org>
Subject: Re: [SOLVED] re(4) incorrect checksum
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On Thu, Jan 11, 2007 at 11:51:51AM +0100, Pietro Cerutti wrote:
> Hi lists,
> ifconfig re0 -txcsum -rxcsum solved the problem....
> 
> Anyway, is this a bug in the driver or in the interface itself?

That is how checksum offloading works.
tcpdump can't see a correct checksum, because it is not calculated 
by the kernel and left for the hardware.
However checksum offloading is broken for re(4) based cards, therefor
it is disabled by default.

-- 
B.Walter                http://www.bwct.de      http://www.fizon.de
bernd@bwct.de           info@bwct.de            support@fizon.de