Ricardo Patara patara at
Mon Feb 2 22:06:06 CET 2009

Hello Erik,
Actually I tried to send an email to point of contact associated with  
the IP block :)
Then I search for some google folks email address with no success.  
Thanks for your promptly answer and attention on this.

In our case, in order to test if the MTU was the problem, we lowered  
it to 1480. But maybe it should be something around the number you  

Just for curiosity, did google tried to contact upstream providers or  
peering to find out if there was any icmp6 filtering in some of the  

thanks again.
   Ricardo Patara

Em 02/02/2009, às 16:59, Erik Kline escreveu:

> You tried to contact us?  I must have missed that email, sorry.
> We set the MTU to 1280 near the server.  We've not had any reported
> MTU problems (knock on wood), to the best of my knowledge.
> 2009/2/2 Ricardo Patara <patara at>:
>> Hi,
>> Just wondering if some of you are using this technique to avoid  
>> problems
>> from someone else accessing your website, for instance.
>> We have our site with ipv6 for a while now, and have received  
>> complaints and
>> we had opportunity to face the same problem several times.
>> This happens when trying to access the site via a tunnel  
>> connection. The
>> browser simply gives a timeout.
>> We think this is related to pmtu and sites filtering icmp6.
>> One of the solutions was to lower down the MTU at the site server.
>> The question is, if this is the solution you did in case you also  
>> faced this
>> problem.
>> I tried to contact someone from google, but with no success.
>> I mention google as we always try when having this  
>> type of
>> problem just to make sure there is nothing "completely" wrong the  
>> network
>> setup.
>> thanks
>> --
>> Ricardo Patara

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