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Date: Sun, 29 Apr 2012 18:47:52 +0400
From: Lev Serebryakov <lev@FreeBSD.org>
Organization: FreeBSD
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Subject: Re: IPv6 MTU discrovery -- how should it work?
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Hello, Lev.
You wrote 29 =D0=B0=D0=BF=D1=80=D0=B5=D0=BB=D1=8F 2012 =D0=B3., 18:35:59:

LS>   When I connect to external server twice, and run tcpdump in one
LS> session for another one, and then try to use second (sniffed) session
LS> for bulk transfer, I can clearly see, that server tries to send IPv6
LS> packets with size 1420 to my local  network  many  times  and  doesn't
LS> get any answer, so it is MTU problem for sure, but how it could be fixe=
d?
 But

server# ping6 -D -s 1420 <host-after-tunnel-with-mtu-1280>

 Works!

 I don't understand, what happens here :(

--=20
// Black Lion AKA Lev Serebryakov <lev@FreeBSD.org>