Re: icmp: 10.1.4.50 unreachable - need to frag (mtu 500) [tos 0xc0]

[Scott Hall <halls@aros.net>]

Thank for the response Chris,

The problem that I see with that solution is that most of the sites, 
which are many by this point, that I have had problems with aren't under 
my control.  Including aol.com, I can just see me trying to convince AOL 
to reconfigure their servers to not set the DF :).  Are there anyother 
work arounds that you can propose? 

thnx,
  --scott

Chris Brenton wrote:

>On Tue, 2004-01-13 at 03:02, Scott Hall wrote:
>  
>
>>So the one question that this whole issue raises in my mind is, Isn't 
>>there anyway to handle the (DF) packets differently?
>>    
>>
>
>Absolutely. Config the stacks on both ends of the connection to _not_
>set DF. This will cause the router at the MTU border to frag the packets
>and will not require an ICMP error packet.
>
>  
>
>>I ask 
>>becuase we have two cisco routers and 6 Adtran routers that handle this 
>>same scenario quietly. 
>>    
>>
>
>I'm guessing if you check the decodes from those packets you will see
>the public rather than the private IP embedded in the payload. I think
>this is what is killing you. This is an old Netfilter bug that I
>*thought* was fixed ages ago.
>
>HTH,
>C
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