From owner-freebsd-net@FreeBSD.ORG  Wed Aug 27 18:55:50 2014
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id 7AAC4A6C
 for <freebsd-net@freebsd.org>; Wed, 27 Aug 2014 18:55:50 +0000 (UTC)
Received: from bravo.jonathanprice.org (bravo.jonathanprice.org
 [5.135.154.174]) by mx1.freebsd.org (Postfix) with ESMTP id 397333B0E
 for <freebsd-net@freebsd.org>; Wed, 27 Aug 2014 18:55:50 +0000 (UTC)
Received: by bravo.jonathanprice.org (Postfix, from userid 58)
 id 24D981E01; Wed, 27 Aug 2014 18:55:43 +0000 (UTC)
Received: from [192.168.1.150]
 (host86-156-241-97.range86-156.btcentralplus.com [86.156.241.97])
 by bravo.jonathanprice.org (Postfix) with ESMTPSA id A52571DFB;
 Wed, 27 Aug 2014 18:55:40 +0000 (UTC)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=jonathanprice.org;
 s=default; t=1409165740;
 bh=0RbnzsEjIRLh117PcrC7vg5vaPdiAX/q+YYbAkbLy8c=;
 h=Date:From:To:CC:Subject:References:In-Reply-To;
 b=i7MKNDOjWqzUxXYlg44Xakfn2KirLI5/NAQ0sFGQEja3oe6Hdf9A9OKFEm2Ri/is9
 uBOboa7fZGHnc6+BGOC4hcpEU987jY8eNHb4l3sVSpRdr9EV1QYZbjJep7Oiu707K9
 /mWqZlxVTrkFcsetktaIXCtEovZIJBiDxO3OpXKs=
Message-ID: <53FE29A8.1000909@jonathanprice.org>
Date: Wed, 27 Aug 2014 19:55:36 +0100
From: Jonathan Price <freebsd@jonathanprice.org>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64;
 rv:24.0) Gecko/20100101 Thunderbird/24.6.0
MIME-Version: 1.0
To: Kevin Oberman <rkoberman@gmail.com>
Subject: Re: Should I be using ipv6_activate_all_interfaces or
 ip6addrctl_policy="ipv6_prefer"
References: <88a42e1006e3fac7508a9419e342f1b2@mail.jonathanprice.org>	<2173103.SJdXL7NPLT@overcee.wemm.org>	<53FD7B34.1050408@jonathanprice.org>	<CAN6yY1uxft_3cTkWV8NTnOai-928DnS3uW-XyD3BwcCvjBKeQw@mail.gmail.com>	<2c1d74944371a4be730ff1b666489467@mail.jonathanprice.org>
 <CAN6yY1vU_aQKhhoKXGPSRQJSPSvz-mqeh3GFkkCg50irbpk-3A@mail.gmail.com>
In-Reply-To: <CAN6yY1vU_aQKhhoKXGPSRQJSPSvz-mqeh3GFkkCg50irbpk-3A@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Cc: freebsd-net@freebsd.org
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.18-1
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net/>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 27 Aug 2014 18:55:50 -0000

> I was over-simplifying and, as you state, any interface explicitly
> configured for IPv6  will have IPv6 disabled. Those with explicit IPv6
> configuration will not be disabled.
>
> Most end-user systems are NOT configured with an address. In most cases
> SLAAC (and, perhaps DHCPv6) along with things like NDP and RTSOL do
> allof hte configuration. If ipv6_activate_)all_interfaces is NO, only
> explicitly configured interfaces will run IPv6. If it i YES, any
> interface with no explicit configuration will auto-configure and run IPv6.
>
> The system I am typing this on is entirely auto-configured as are almost
> all Windows systems running 7 or 8. (Maybe Vista, too. Don't recall.)
> --
> R. Kevin Oberman, Network Engineer, Retired
> E-mail: rkoberman@gmail.com <mailto:rkoberman@gmail.com>

Ah, thanks, that makes sense.

Would that mean that a line such as 'ifconfig_IF="DHCP"' would not count 
the interface as being explicitly configured? I haven't looked into 
SLAAC or DHCPv6 configuration yet, so I'm not sure if either of those 
require a line like the one above.

I couldn't word that particularly well. Basically, my question is, does 
any "ifconfig_IF_..." line count IF as being explicitly configured, or 
is it just interfaces with statically assigned addresses?

Thanks,
Jonathan.