If ISC was to publish in the DNS
www.isc.org. 10M IN AAAA 2001:4f8:0:2::d ; exists today
www.isc.org. 10M IN AAAA FC01:4f8:0:2::d
and you happened to have a machine with local addresses
FC01:4f8:0:2::d.
You would be unable to reach www.isc.org from any machine
receiving your ULA prefix as a consequence of the address
selection rules.
This is the harm that can be caused when you publish a
LA ULA.
If you don't have MUST NOT you don't have a way to point
blame when things go wrong. With MUST NOT you can say
please remove the address you are in violation of RFC XXXX.
2001:4f8:0:2::d is assigned by forcing the LL address then
using auto assignment to get the other prefixes. It is
done this way so it won't change with hardware changes.
I expect other sites will do similar things to provide stable
addressing to their external machines. Collisions in addresses
get much more probable when you start assigning the local parts
by hand.
--
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: [EMAIL PROTECTED]
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[EMAIL PROTECTED]
Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
