Re: DHCPv6 address used when M or O bit is set

Dominik Elsbroek <dominik.elsbroek@gmail.com> Wed, 04 April 2012 14:38 UTC

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Date: Wed, 4 Apr 2012 16:38:45 +0200
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Subject: Re: DHCPv6 address used when M or O bit is set
From: Dominik Elsbroek <dominik.elsbroek@gmail.com>
To: Fernando Gont <fgont@si6networks.com>
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Hi Fernando,

> What's removed is the corresponding text, not the bits. See page 19 of
> RFC 4861: the bits are still there.
>

In RFC4862, Appendix C there is one point:

Removed the text regarding the M and O flags, considering the
      maturity of implementations and operational experiences.
      ManagedFlag and OtherConfigFlag were removed accordingly.  (Note
      that this change does not mean the use of these flags is
      deprecated.)

Not sure how to interprete this. Perhapts I am just missing a link,
but M and O flag in RFC 4861 doesn't tell how to do SLAAC, e.g. when
the nameserver should be determined by DHCPv6-server.


>
>> They don't even longer exist, but still
>> exist?
>
> I'm curious about why the corresponding text was removed. In particular
> when at the time (2007) the DNS options was not yet widely implemented,
> and hence you *needed* DHCPv6 to learn the addresses of recursive DNS
> servers dynamically.
>

I am still very curious which address a client should use, if the O or
M flag is set, to find a DHCPv6 server.

Cheers,
Dominik