Re: ne2000 / Checksum errors
Mon, 07 Apr 1997 17:55:24 +0200

Erik M Pennebaker <> writes:
>These come often and in big spurts. The hex ip addresses always corelate
>to a session that is having problems...
>My question, than is:
>1) Do the 2.0 kernels not log TCP checksum errors, and I've been getting
> errors before the PCI ne2000/2.1 kernels, and not noticing? I've
> gotten 20 ICMP checksum errors in total on the 2.0.28/ISA card machine
> since Jan. 22; nothing like above.

TCP checksum errors are not logged in any way on the 2.0.X kernels.
In fact, there are a whole bunch of places that packets can get dropped
in both kernels without getting counted as dropped in any statistics.
I've been thinking a bit about what we should do about this, but I
haven't reached any definite conclusions. If you want to check if
you are loosing packets to bad TCP checksums in 2.0.X I can give
you a little patch that sets up the 2.0.X kernel to report bad packets.

Eric Schenk                               www:
Dept. of Comp. Sci., Lund University          email:
Box 118, S-221 00 LUND, Sweden   fax: +46-46 13 10 21  ph: +46-46 222 96 38