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Re: IPV6 router works, but clients fail

>>>>> "rm" == Roy Marples <> writes:

    rm> I needed to clamp max-mss in pppoe0 to 1432. It used to be
    rm> 1452, which I recall was needed for my wireless
    rm> clients. Probably the extra overhead of IPv6.

The PPPoE MTU problem should not exist on IPv6, and at my site where I
have <1500 links to the internet I didn't have to change mss-scrubbing
smaller for IPv6.  It's possible you are creating the PPPoE problem
yourself somewhere by blocking ICMPv6 'too-big' packages.

You should never find you need the mss scrubbing to reach the Internet
period---if you do, you must be blocking too much ICMP on your end.
The symptom of needing smaller mss scrubbing is that a few of other
people's misconfigured sites on the Internet don't work, just a few
not all.  I wish you would have a look to your ICMP rules to avoid
publishing bad examples which will infect other sites and spread the
PPPoE problem.

The way it's documented/supposed to work, you must either pass too-big
/ frag-needed ICMP, *or* use 'keep state' TCP rules which pass that
ICMP implicitly.  The way it actually works, I'm not so sure.

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