Re: RA "requires" DHCPv6 ?

Karl Auer <> Sat, 31 March 2012 22:46 UTC

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Subject: Re: RA "requires" DHCPv6 ?
From: Karl Auer <>
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On Sat, 2012-03-31 at 21:43 +0200, Fernando Gont wrote:
> > Or you could use one's statically assigned address. 
> Oh, yeah. And you could have opted to not send the RS in the first
> place... and what? :-)

Um, I'm not sure why we're arguing. I'll still see unsolicited RAs at
regular intervals, and I'll see RAs sent because of other hosts' RSes.
Also, the RA contains lots of useful stuff even if I am not doing DHCPv6
- for example if I want to do SLAAC I'll still be sending an RS. I don't
think my question was stupid. I'm sorry you do.

> -- However, particularly in the case in which the local router wants
> you to use DHCPv6, they could easily block addresses that have not
> been leased by the DHCPv6 server. SO, at the end of the day, you're at
> its mercy.

Absolutely. The question was just whether or not a host was *required*
"O" flags and do DHCPv6, not whether it would be practical or
appropriate to do so.

> We were assuming the "regime" was controlling the local link. If they
> do, its up to them whether there are other routers on the link and/or
> whether RAs are allowed to flow on that link.

My question was unrelated to the discussion about "the regime". That's
why I started a new thread with a new subject line, and quoted only that
exact part of your statement where you said "requires you to do

And I was not saying you were wrong - I was seeking clarification (from
you or anyone), because IMHO it is not clear from the RFCs whether a
host SHOULD or MUST honour the "M" and "O" flags (obviously it MAY :-). 

Regards, K.

Karl Auer (

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