Working on howl port

[Andrea Campi]

On Sat, Dec 11, 2004 at 04:41:17AM -0500, Chuck Swiger wrote:
> Andrea Campi wrote:
> [ ... ]
> >The way I'm addressing this is to have autoipd use SIOCAIFADDR
> >and manage exactly one address in the 169.254/16 block. This
> >means you will ALWAYS have an IP address in that range; if you
> >also run dhclient, you might have an additional IP and a default
> >route.
> >
> >Thoughts?
> 
> See http://files.zeroconf.org/draft-ietf-zeroconf-ipv4-linklocal.txt:
> 
> 1.9.  When to configure an IPv4 Link-Local address
> 
>    Having addresses of multiple different scopes assigned to an
>    interface, with no adequate way to determine in what circumstances
>    each address should be used, leads to complexity for applications and
>    confusion for users.  A host with an address on a link can
>    communicate with all other devices on that link, whether those
>    devices use Link- Local addresses, or routable addresses.  For these
>    reasons, a host SHOULD NOT have both an operable routable address and
>    an IPv4 Link-Local address configured on the same interface.
> 
> ...but there is more there to read.  It's fine to let an interface have a 
> 169.254/16 IP and a "real" IP (assigned by DHCP, the user, etc) for a 
> little while during transitions, but not forever.

Uhm. Yes, I can see the point about added complexity, and that was
my main concern as well. I forgot that the RFC explicitely mentioned
this however.

Still, what's worse, having two correct but potentially confusing
addresses, and everything still working; or having DHCP and autoipd
fighting over which one determines the one and only IP address? I'll
have to check how Mac OS X handles this, but unless we merge zeroconf
in dhclient (ugh!) or vice versa, I don't see an alternative which is
as convenient for the user. Do you?


Bye,
	Andrea

-- 
            Give a man a fish and you feed him for a day;
     teach him to use the Net and he won't bother you for weeks.