[131338] in North American Network Operators' Group
Re: IPv6 fc00::/7 =?UTF-8?B?4oCU?= Unique local addresses
daemon@ATHENA.MIT.EDU (Mark Smith)
Fri Oct 22 03:55:33 2010
Date: Fri, 22 Oct 2010 18:25:18 +1030
From: Mark Smith <nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org>
To: Karl Auer <kauer@biplane.com.au>
In-Reply-To: <1287723128.10216.182.camel@karl>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Fri, 22 Oct 2010 15:52:08 +1100
Karl Auer <kauer@biplane.com.au> wrote:
> On Thu, 2010-10-21 at 21:05 -0500, Jack Bates wrote:
> > On 10/21/2010 8:39 PM, Ray Soucy wrote:
> > >
> > > How so? We still have RA (with a high priority) that's the only way
> > > DHCPv6 works. I guess there is a lot of misunderstanding about how
> > > DHCPv6 works, even among the experts...
> >
> > Actually, the last I checked, there are implementation of DHCPv6 without RA.
>
> I'll go out on a limb here and say that RA is not needed for DHCPv6.
>
RAs are still needed to convey the M/O bit values, so that end-nodes
know they need to use DHCPv6 if necessary. As there are two address
configuration methods, there is always going to be a need to express a
policy to end-nodes as to which one they need to use.
> A DHCPv6 client multicasts all its messages to the well-known
> all-relays-and-servers address. A client needs only its link-local
> address to do this. The relay (or server if it happens to be on the same
> link) can thus talk to the client in the complete absence of RA.
>
There isn't a method to specify a default gateway in DHCPv6. Some
people want it, however it seems a bit pointless to me if you're going
to have RAs announcing M/O bits anyway - you may as well use those RAs
to announce a default router too.
Regards,
Mark.
