How to generate IPv6 RA without any prefixes?

[Siquijor Philips]

On Mon, Nov 22, 2010 at 4:01 PM,  <sthaug at nethelp.no> wrote:
>> > I would like to get rtadvd to send RAs completely *without* a prefix
>> > info option. My Juniper routers at work can do this just fine...
>>
>> Oh I see. I haven't tried this case with FreeBSD configuring RA with
>> default route info only. So, how your Juniper router coordinate your
>> DHCPv6 server to inform the hosts or nodes where to get prefix info
>> since then your router wasn't configured with pinfoflags options?
>
> The router sends RAs with the "managed" flag, in the RA header (not
> connected to any specific prefix). This tells the clients that they
> should attempt DHCPv6 configuration.
>
>> Or
>> the hosts are just configured with DHCPv6 client informing directly
>> the DHCPv6 server for IPv6 address info while its default route is
>> obtainable via RA through SLAAC?
>
> The default route and the "managed" flag come from RA. The rest from
> the DHCPv6 server.
>
> Some of us would *like* DHCPv6 to be able to work without RA - but that
> is a different (religious) discussion.
>
> Steinar Haug, Nethelp consulting, sthaug at nethelp.no
>

Thanks for the explanation Steinar, this is clear to me now. So, as
what other folks have suggested, I think you can proceed with issuing
a PR to this.