K tejto teme som nasiel este toto:
If you use the no-advertise, the prefix will not be included on the RA. What's the problem with that? Host not only use the prefix on an RA to generate addresses for SLAAC, but also to know which destinations are local and which ones aren't. Check RFC-4861, section 6.3.4. If the router advertise the prefix with the on-link flag set, hosts will consider destinations within the prefix as being present on the link - and will do NS to reach them, forward directly to destination. If you do NOT advertise the prefix, then the host has no clue that the prefix is local - and will forward packets to destination within its same prefix to the default router. Remember that DHCPv6 doesn't provide any information about the prefix length - just the address.
So unless you want to see a lot of redirects from your router to your DHCPv6 clients - advertise the prefix, but with no-autoconfig :)