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Date: Tue, 9 Oct 2018 07:16:44 +0700
From: Victor Sudakov <vas@mpeks.tomsk.su>
To: Kevin Oberman <rkoberman@gmail.com>
Cc: citrin+bsd@citrin.ru, freebsd-net <freebsd-net@freebsd.org>
Subject: Re: why rtsold ?
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Kevin Oberman wrote:
> > > > When running FreeBSD as an IPv6 host im SLAAC mode, is
> > > > "rtsold_enable=YES" really necessary? I did not enable rtsold and IPv6
> > > > still works fine only with
> > >
> > > rtsold is needed to write DNS server address from RDNSS RA option to
> > > /etc/resolv.conf
> > >
> > > man rtsold
> > > /-R
> >
> > On my test IPv6-only host, /etc/resolv.conf was successfully created
> > without any explicit "rtsold_enable=YES".
> >
> > --
> > Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
> > 2:5005/49@fidonet http://vas.tomsk.ru/
> >
> Remember that DHCPv6 can provide DNS server and other information even when
> SLAAC is used for address configuration. If it is, it is possible to run
> SLAAC without rtsold, but it may not prove stable as it is not possible to

The case is that my IPv6 lab (actually a number of FreeBSD hosts in
bhyve) does not have a DHCPv6 server. Still, the /etc/resolv.conf on
IPv6-only hosts is successfully populated from the router.  The latter
is running only rtadvd with the following config:

bridge0:rdnss="2001:470:20::2,2001:4860:4860::8888,2001:4860:4860::8844":dnssl="sibptus.ru":

Magick?

-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
2:5005/49@fidonet http://vas.tomsk.ru/