option 212 for 6RD

Tassos Chatzithomaoglou achatz at forthnetgroup.gr
Sun Jan 20 17:29:40 CET 2013

I had a quick look and it seems you configure a general mss value (pta/l2tptcpmss-adjust
X) which refers to the IPv4 value, and the IPv6 one is automatically calculated from it.


Sander Steffann wrote on 19/1/2013 18:26:
> Hi,
>> Ivan, i have the impression that in the newest BRAS/BNG platform (ASR9k, so it's actually
>> IOS-XR, not IOS), the router uses automatically the IPv4 TCP MSS configured value minus 20
>> bytes as the IPv6 TCP MSS value.
> And do MSS clamping automatically without anybody configuring it? That would be very annoying...
> I hope not,
> Sander

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