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Re: Help....IP Header Checksums are all set to zero.... [7:85993] posted 03/17/2004
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garrett.allen@xxxxxxxxxxx wrote:

> it may not be the same situation but we had incorrect tcp checksum's that
> ultimately were due to a configuration setting on the nic.  the driver for
> the nic allows for "tcp/ip checksum offload".  it was set to "tx". 
> disabling that feature eliminated the problem.

That wasn't a problem, just the NIC doing what it was told to. Your 
analyzer captured the frames before the NIC put in the correct IP 
checksum, so they were wrong according to your analyzer.

Capturing the traffic on another machine would probably have shown that 
the checksum on the wire was OK.

		Regards,

			Marco.




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