[erlang-questions] IPV6_V6ONLY

Kenji Rikitake <>
Tue Sep 7 06:41:57 CEST 2010

In the message <>
dated Tue, Aug 24, 2010 at 09:56:07AM +0200,
Raimo Niskanen <> writes:
> It seems the situation has changed since Stevens' Unix Network Programming
> - The Sockets Networking API, third edition. There it seems one of the strong
> points of a IPv6 socket is that it accepts IPv4 connections _unless_ the
> IPV6_V6ONLY socket option is set.
> Where can these network community discussions be followed where
> can one find a motivation to why FreeBSD has diverged from Stevens' book
> (if that is the case)...

See RFC3493 Section 5.3, and

My opinion is that just because Linux does it is insufficient for making
it as the default for the IPV6_V6ONLY behavior.  And even on FreeBSD you
can make a choice by sysctl param of "net.inet6.ip6.v6only" (see
inet6(4)). I'd rather want to leave the choice to the operating system.

Kenji Rikitake

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