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Re: IPV6 router works, but clients fail

Miles Nordin wrote:
"rm" == Roy Marples <> writes:


oh you are fucking kidding me.

well, the problem is still on your end, though.  It's just in your
modem instead of in your PF rules.

Could you try to get a different modem?  I have a BroadXTent modem
that grabs its address over PPPoE, then hands the address it grabs to
the connected host using DHCP with a short lease.  If you had a modem
like mine which used PPPoA instead, then in PPPoA mode you could get
the full 1500 mtu, no?  Some googling found this:

Another alternative is to use Cisco CPE like 1721+WIC-1ADSL or 857 and
terminate the IPv6 on the Cisco.

What's the point of this translation to PPPoE that Matthias says his
modem is doing?  It seems really odd.  I'd think if the modem were
speaking PPPoA it would certainly handle all the passwords and
terminate the PPPoA on the modem, after which it would either act as a
normal router doing its own NAT, or else at the weirdest pass to you
its local PPPoA IP in that nonstandard proxyarp/fakeDHCP way of which
my BroadXtent modem is capable.

This is the modem recommended by my ISP so can I get native IPv6 working. AFAIK it's not possible with my old modem, a DrayTek Vigor 2600 which oddly enough is listed in your link.

At the time of purchase, no ADSL modem in the UK could handle IPv6 that I could see, except for Cisco routers which are well outside of my price range by a few hundred pounds. So going for the Vigor100 for a PPPoA PPPoE bridge was a no brainer as then my server could handle PPPoE + IPv6.

Is it for certain the modem is really converting PPPoA<->PPPoE like
this, and not just that the DSLAM in the CO works in a variety of
modes (oA, oE) among which you can choose, and the oE mode is broken
for v6?  I hope it's the modem that's broken not the DSLAM since you
can swap the modem out, but I doubt the story because this is the
first I've heard of a modem doing that.

I'm pretty sure the UK is PPPoA only so it would have to be a bridge.
Maybe there are some settings on the vigor I can tweak, or maybe try and adjust the PPPoE MTU to 1500?

I suppose you'll ignore this and keep using the mss clamping.  but
FYI, it is really broken.

No, as it really is a hack.
I'll probably end up just enforcing an MTU of 1492 on the network as I control all the client side equipment. I just hope that my games consoles obey the MTU DHCP setting :)



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