[arch-general] ipv6 only half working

[David Rosenstrauch]

On 07/23/2018 12:42 PM, Giancarlo Razzolini via arch-general wrote:
> Em julho 23, 2018 12:46 David Rosenstrauch escreveu:
>>
>>
>> I'm really stumped as to how ipv6 could partially fail like this only 
>> on specific apps.  Seems like it should either completely work or 
>> completely fail.
>>
>> Anyone have any idea what might be happening here and/or how to fix?
>>
> 
> Hi David,
> 
> If ping works, but bigger packet things don't, then you might have some 
> PMTU
> issue that is only affecting IPv6. You can confirm this with a tcpdump 
> trace
> quite easily. Look at the packet sizes. Both things you've mentioned 
> (opening a
> web page and updating antivirus) are http, and it does usually use the 
> maximum
> transmission unit.
> 
> Regards,
> Giancarlo Razzolini


Makes some sense.  I'll take a look on my router and see if perhaps I'm 
inadvertently blocking some ICMP packets.

That said, one thing doesn't quite seem to fit with this explanation:

Why would "curl -6 ipv6.google.com" while "w3m -6 -dump ipv6.google.com" 
fails?

Thanks,

DR