Using an *external* DHCPv6 server for prefix-delegation in conjunction with PPPoE

[Per Carlson]

Hi Frank.

> I'm trying to get our lab bench Cisco 7206VXR (running 12.2(33)SRE2) to
> cooperate with me in regards to using an external DHCPv6 server (ISC v4.2)
> to delegate IPv6 prefixes to CPE.
>
> Any ideas?  Is anyone else doing this?!?

I've got similar results in a somewhat different setup:

interface GigabitEthernet0/2.601
 encapsulation dot1Q 601
 ipv6 enable
 ipv6 dhcp relay destination FD00:8C0:199::199

With this config the relay (7200/NPE-G2 running SRD/SRE) also sends
empty link addresses towards the DHCPv6 server (ISC 4.1 in my case).

The only way I managed to get DHCP-PD working was adding an IPv6
address on the interface + running SLAAC on the CPE.

Reading the RFC (http://tools.ietf.org/html/rfc3315#section-20.1.1)
this behaviour is expected. The Interface-Id option is populated, but
AFAIK ISC can't use that when selecting the scope.

-- 
Pelle

RFC1925, truth 11:
 Every old idea will be proposed again with a different name and
 a different presentation, regardless of whether it works.