Re: [Autoconf] Using DHCPv6 without link-local? Support only EUI-64interfaces?

[Ulrich Herberg <[e-mail]>]

Fred,

On Mon, Aug 2, 2010 at 7:31 PM, Templin, Fred L
<[e-mail]> wrote:
>[...]
>>
>> I have tried that a while ago. It works with some limitations (see below).
>>
>> >
>> > I think it could work this way:
>> > 1) Node queries with link-local to All_DHCP_Relay_Agents_and_Servers.
>> > 2a) Node acts as also relay and queries with ULA (site-local) to All_DHCP_Servers.
>>
>> Do you mean that a node is DHCP client and relay in the same time?
>> That is not possible according to RFC3315, which says (i) in section
>> 15.13 "clients MUST discard any received Relay-forward messages"
>
> The client function would never see a Relay-forward, because
> that is generated by the relay function and sent to either the
> unicast address of a server or All-DHCP-Servers multicast. Maybe
> you meant section 15.14 "Clients and servers MUST discard any
> received Relay-reply messages"? But, it is the node's relay
> function (and not the client function) that gets the
> Relay-reply so this is not in violation of the spec.

Thanks for that clarification. If this demultiplexing is possible,
than it should indeed not be a problem. Is that explicitly mentioned
in the RFC?

>
>> and
>> (ii) section 15.3 "servers and relay agents MUST discard any received
>> Advertise messages".
>
> The node's client function (and not the relay function) is the
> one that gets the Advertise message when 4-message exchange is
> used; the relay function sees only the Relay-reply and then
> forwards the Advertise on to the client function.

Same comment as above.

> Also, in
> 2-message exchange there is no Advertise message.
>
> Fred
> [e-mail]

Ulrich

>[..]