In message <20050423062817.GH27204@che.ojctech.com>David Young writes

>On Fri, Apr 22, 2005 at 04:47:11PM -0700, Bill Studenmund wrote:

>> We thus at present have an
>> ambiguity as to which IP to choose. 

So Bill says. But the *BSD stack and derivatives have a _long_ history
of ``pick the first one''.  I know of several pieces of code which
relies on that ordering to implicitly distinguish ``primary'' or
``first-class'' IP addresses from ``secondary'' addresses.  David's
proposal will break such code.

Tho' I dont know if it works anymore on NetBD, with hashed lookup of
local-IP-addrs it certainly does on other BSD derivatves. If it truly
isn't predictable on NetBSD, then that strikes me as a darn good
reason to distinguish first-class local addresses from
explicitly-marked secondary or "alias" addresses.

That will solve David's problem, and (unlike David's proposal) it
isn't a half-arsed kludge.



>So how is adding policy to pick one of
>> them going to break valid uses of IPv4? Those uses have no assurances at 
>> present, so how will they get something they might not have gotten now?


>If anybody can think of a case, please let me know!

For the Nth time: consider someone stuck using nonroutable addresses,
say 192.168.x.y, as their `private' address and using (say) 10.x.y.z
as a campus-wide `public" address.  Or, consider someone relying on
current(?) implicit `ordering' of addresses.

David, what's going on here? Are you not seeing these examples, are
you deliberately ignoring them, or is something else going on?