Blackholing delegated prefix (Was: Using an *external* DHCPv6 server for prefix-delegation in conjunction with PPPoE)

[Zuleger, Holger, VF-DE]

Btw,

> It's even better: You can directly assign a PD address on the 
> WAN interface:
> 
> interface FastEthernet0/1.1600
>  encapsulation dot1Q 1600
>  ipv6 address PREFIX ::/64 eui-64
>  ipv6 enable
>  ipv6 nd autoconfig default-route
>  ipv6 dhcp client pd PREFIX rapid-commit
> end

does anyone know how I can setup a null route for the delegated prefix?
Something like
	ipv6 route PREFIX ::/48 null 0

It seems to be best practice to avoid routing loops (see WPD-6 of
http://tools.ietf.org/html/draft-ietf-v6ops-ipv6-cpe-router-09#page-10),

but I don't know how to configure this with DHCPv6-PD.
 

Many thanks
 Holger