On 2/10/2013, at 6:38 PM, Lindsay Hill
Some disagree with that, and say that ULA should only be used if you NEVER want to talk to any public Internet systems:
http://www.howfunky.com/2013/09/ipv6-unique-local-address-or-ula-what.html
I've skim read that article, and it seems to misunderstand the application ULA was intended for, and the guy seems to talk about things in a way that indicates a poor understanding of the topic. ULA is for static (or, long term) internal addressing for access to internal systems. It has higher precedence in the default address selection tables, etc. etc. If you also want Internet access, you must *also* have globally assigned addresses, *at the same time*. These addresses may change as your Internet connection flaps around, or whatever - so you have to have the ability to do that. RA has a prefix expiry thing where you can set the lifetime of a prefix to 0 to make it expire immediately (I think, maybe 0 means indefinite and you have to set it to 1s or whatever. *handwaving about details*), and DHCPv6 has an update message if you want to roll stateful and give people new leases when your PD prefix from your ISP changes. The benefit of using ULA (and it is an optional thing), is you can use internal DNS on your AD server (or whatever), and you can do whatever other internal things you want where you need static addresses. Maybe you've got some permanent video conferencing system or something, and you don't want to bounce it or whatever. More hand waving. You still need global address(es?) for Internet access. The two are not mutually exclusive. -- Nathan Ward