Help with DHCPv6 client-identifiers

[Ted Lemon]

On Nov 19, 2011, at 4:05 PM, "Alex Bligh" <alex at alex.org.uk> wrote:
> Autoconfig is quite inflexible in terms of addressing and netmasks which
> can be used. In particular, use of EUI64 means you end up giving the client
> a much bigger subnet than they need, and it is hard to allocate >1 IPv6
> address per NIC (i.e. per MAC) using this scheme without wasting yet more
> space. What we'd really like is to be able to allocate a fixed number
> of least significant bits (say 24) as "index of IP on one NIC", then the
> next (say 24) as "index of NIC on vLAN". Each vLAN would then get a /80.
> We could do have done that with DHCP or similar if it worked.

Then it is indeed fortunate that DHCPv6 doesn't do what you want.   Using prefixes wider than /64 breaks IPv6.   That's why SLAAC doesn't do it.