dhcpv6

[Patrik Lahti]

>      a) How can I view DUID for Linux and XP computers, I couldn't 
> find in regedit?
On Linux you look for it in the leases file. I have no idea about XP...
>      b) where is the DUID stored, will it change when the operating 
> system disk formatted-reinstalled? It's a big problem for my cooperate 
> database.
See RFC 3315 about how DUIDs are formed. They are usually based on MAC 
addresses (at least part of them).
> so RA is mandatory.
Yes, this is the IPv6 way.
> is there a thought to change IPv6 RFC and ISC-dhcp in future, for 
> router address assigning?
No, I highly doubt that's going to change, but you're better asking on 
IETF lists about RFC changes.

HTH
/P