Re: problem configuring squeeze

Hi, 

On Mon, May 16, 2011 at 06:55:00PM -0300, Henrique de Moraes Holschuh wrote:
> On Mon, 16 May 2011, Bjørn Mork wrote:
> > Henrique de Moraes Holschuh <[email protected]> writes:
> > > On Mon, 16 May 2011, Bjørn Mork wrote:
> > >> I don't think that will be much of a problem, given that you probably
> > >> have full control over the vserver network.  Routing on longer prefixes
> > >> than /64 work just fine, and there are many advocating using /126 or
> > >> /127 for point to point links.
> > >
> > > /126 is fine.  /127 is not really a good idea beacause of DAD, and it is
> > > not like using /126 instead of /127 is going to waste too much valuable
> > > address space (unlike /31 versus /30 in IPv4).
> > 
> > No, waste is not an argument.  The main argument for both /127 and
> > /126 is to avoid having unused addresses on a link.  But /126 will still
> > leave one adress, which is why some prefers /127 instead. Although this
> > does mean that you have to ignore the router anycast address.
> > 
> > > http://tools.ietf.org/html/rfc3627
> > 
> > Well, that's one informational opinion.  There's also the recent
> > standards track opinion: http://tools.ietf.org/html/rfc6164
> 
> Heh.
> 
> > The nice thing about standards is that there's so many of them :-)
> 
> Well, as long as you request that the equipment supports rfc6164, it
> certainly is far more sane than running DAD on a /127.
> 
> But we need also to check that Linux supports rfc6164 and doesn't do
> anything too idiotic.  It certainly can screw up rather nicely on IPv4 /31
> when ifconfig is used (instead of iproute) because it does not EINVAL the
> broadcast address (requested by stupid ifconfig) as it should nor considers
> a IPv4 /31 link to be point-to-point in the first place.

I had tested this on an tunnel link with an /127 and it fails. With an /126
all works fine. So, i think  at least on squeeze this is currently no option.
Haven't tried wheezy or sid.

cheers, 
tim


-- 
Tim Weippert
http://weiti.org - [email protected]
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