[Fedora-xen] TCP checksum corruption

[Daniel P. Berrange]

On Tue, May 08, 2007 at 01:00:32PM -0500, Mike McGrath wrote:
> Daniel P. Berrange wrote:
> >Ok that makes absolutely no sense to me now :-)  Everytime I hit it I was
> >able to solve it eventually by setting 'tx off' on some combo of devices.
> >The RHEL-5 Dom0 kernel also already has the neccessary fixes in which is
> >even odder that it doesn't work for you. 
> >  
> 
> So the question is where to proceed from here?  I can tcpdump on the 
> bridge, peth and the domu host to see the errors.

Actually tcpdump showing errors does not neccessarily mean that there are
errors! If checksum offload is enabled, then you expect tcpdump to show
errors, because the checksum is not filled in by the OS - its left up to
the physical NIC. If you've turned 'tx off' on absolutely every device
then, tcpdump ought to show correct checksums though.

Dan.
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