Subject: Re: `ifconfig wm3 ip4csum` creates bad cksums via tcpdump
To: Paul Goyette <email@example.com>
From: Charlie Allom <firstname.lastname@example.org>
Date: 05/19/2007 20:48:58
On Sat, May 19, 2007 at 11:24:14AM -0700, Paul Goyette wrote:
> If the tcpdump is for an outbound packet, this is expected. Since you told
> the driver that the hardware does checksum, the software doesn't
> calculate one; it just sets it to zero. Then tcpdump gets its copy of
aha - thank you!
> the packet and dumps that out. Sometime later, the hardware gets to do its
> thing and calculates the correct checksum.
> Get the tcpdump from the receiving side and verify there that the csum is
indeed. all seems well at the end of the day :)