Re: {SPAM?} Re: IPv6 Deployment for the LAN

[Owen DeLong <owen () delong com>]

On Oct 22, 2009, at 12:23 PM, Ray Soucy wrote:

> > This to me is one of the least credible claims of the RA/SLAAC crowd.
> > On the one hand we have carriers around the world with millions and
> > millions of customers getting default routes and other config through
> > DHCPv4 every day. And most of the time it actually works very well!
> >
> > On the other hand we have RA/SLAAC with a vastly smaller customer
> > base, vastly less real life testing - but which is still claimed to
> > be so much better that DHCPv6 is not *allowed* to get a default route
> > option.
>
> If the argument against RA being used to provide gateway information
> is "rogue RA," then announcing gateway information though the use of
> DHCPv6 doesn't solve anything.  Sure you'll get around rogue RA, but
> you'll still have to deal with rogue DHCPv6.  So what is gained?
Apparently you missed the entire message he responded to about the
number of things specified by DHCP and the differences between the
groups in control of the routers vs control of the hosts/servers and the
actual administrative groups in charge of each?

> I guess I'm not really seeing the case here.  Are people really making
> use of DHCP to provide hosts on the same network with different
> default gateway information?  If so, why?
Yes.  A number of different application and business requirements. Some
I can go into easily (load balancing among different routers, routers  
owned
by different departments, etc.), some are proprietary to my clients  
and I can't
give enough details without violating NDA.

> Or is it that you want IPv6 to be a 128-bit version of IPv4?  RA is a
> good idea and it works.  You can add options to DHCPv6, but I don't
> see many vendors implementing default gateway support unless you can
> make a real case for it.
The assignment of gateway information to the host belongs in the hands  
of the
systems administrators and not in the hands of the people running the
switches and routers in many organizations.

With router information assigned through DHCP, this is preserved.   
With it
being assigned by the router, it is not, and, in fact, the case.  With  
DHCPv6
unable to assign router information you lose that administrative  
boundary
and take away a systems administrators control over their hosts and hand
it to the networking group.

> My fear is that your goal is to do away with RA completely and turn to
> DHCPv6 for all configuration.  RA is actually quite nice.  You really
> need to stop fighting it, because it's not going away.
Not at all.  People are not saying RA has to go away.  They are saying  
we
need the option of DHCPv6 doing the job where we do not feel that RA is
the correct tool.

More tools are good.  Replacing one tool that works today with a new  
tool
that is arguably inferior in many real world cases, on the other hand,  
is
not so good.

Owen