Subject: Re: skb_checksum_help

From: David Coulson <[email-masked]>
Date: Mon, 24 Jan 2005 10:27:47 -0500

Thomas Graf wrote:

> After inspecting your iptables rule set I think it is a general UDP DNAT
> problem under some circumstances. Some defragmentation weirdness in
> prerouting might be invovled. It would definitely help to have a dump
> of a complete ip fragments sequence causing this bug but I can't tell
> what exactly is the cause just now so yes it might be a good idea to
> limit the dump to the above subnet and hope the dodgy traffic comes
> from the same subnet again.

cr1:~# tcpdump -nxxli vlan102 net 211.32.117.0/24 and port 53 > tcpdump.txt

I assume that 'xx' is sufficient to dump all of the packet/link 
information we need?

David

-- 
David J. Coulson
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