From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan B db@cyclonehq.dnsalias.net Date: Sat, 10 Feb 2001 04:52:56 +0000 Subject: [LARTC] HTTP only works on second try from doublely NAT'ed Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lartc@vger.kernel.org 
At 08:00 PM 2/1/2001 -0800, Dan B wrote:

>> > Here's my setup:
>> > ---------------
>> > Internet
>> >   |
>> >   |
>> > DSL Router (64.x.x.130 external, and 10.0.0.250 internal)
>> >   |
>> >   |
>> > Linux Box  (10.0.0.251 internal/mapped to external 64.x.x.131 by DSL 
>> router
>> > NAT)
>> >   |
>> >   |
>> > Windows98  (10.0.0.122 internal - NAT'ed to 64.x.x.131 by Linux Box & DSL
>> > router before reaching Internet)
>>
>>Are the DSL Router, the Linux Box and the Windows 98 machines all on a
>>single subnet, of interface? In that case the Linux box may be sending out
>>ICMP Redirects. Linux machines might react instantly to those redirects,
>>Windows only on the second try?
>>
>>Use the great tool tcpdump of ethereal to find out what is exactly being
>>sent over the wire.
>>
>>Regards,
>>
>>bert hubert
>
>
>It's been a few weeks for me to think about my problem, and I think I 
>finally figured out what you meant by what you said, Bert.  I think my 
>problem is the linux box is trying to NAT between two interfaces even 
>though they are on the same subnet.  (duh! tcp/ip 101).
>
>So I'm going to try changing the Linux box to 10.0.0.251/255.255.255.248, 
>and the windows98 box to 10.0.0.122/255.255.255.128, and see if the NAT 
>will work correctly after that.

That fixed it. :-) (I gotta remember that you can't NAT / route between two 
computers on the same subnet very well).


Dan Browning, Cyclone Computer Systems, danb@cyclonecomputers.com