lkml.org 
[lkml]   [2006]   [Oct]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: Networking messed up, bad checksum, incorrect length
Date
Carlos Velasco <lkml@newipnet.com> wrote:
>
> 03:12:22.484863 00:13:21:cc:54:a6 > 00:0d:bc:a0:e2:82, ethertype IPv4
> (0x0800), length 12546: 192.168.128.182.59061 > 193.147.150.12.25: .
> 68786:81266(12480) ack 228 win 40 <nop,nop,timestamp 9644391 425655748>
>
> LENGTH: 12546 !!

> But still worse, I wrote the full sniffer traces to a file for further
> analysis with Ethereal, and there I see that not only these long packets
> are above MTU, all they have bad TCP checksums.

These packets look like normal TSO packets. Linux will send a
packet containing more data than fits in a packet to the NIC. The
NIC will then segment the packet for us.

In order to see what really goes out, you'll need to run a packet
dump beyond the NIC.

If that is not possible, you can try disabling TSO with ethtool -K.

Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-10-27 05:39    [W:0.035 / U:18.104 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site