Re: [Bugme-new] [Bug 28512] New: IPv6 SLAAC address preferred over static one as source address

From: Andrew Morton <akpm@linux-foundation.org>
Date: Mon, 7 Feb 2011 15:20:48 -0800

quoted

SLAAC addresses will have a limited preferred lifetime (as defined by the
router), static addresses will usually have an unlimited preferred lifetime
(0).  So it makes a lot of sense to take this preferred lifetime into account
for source address selection (how is it otherwise "preferred"?).

This is debatable.

One could just as easily say that an address with a shorter preferred
lifetime has been revalidated more recently, and therefore is more
likely to be uptodate, valid, and lead to a usable path.

I think the lack of specification for the final tie-breaker in the RFC
was intentional :-)

The specification has to address this, and until the situation is more
clear cut than it is now I don't see any benefit for changing Linux's
behavior.  Especially since there is a configuration based workaround
which works for people in the short-term.

But I'm willing to be convinced, and those wanting to convince me can
post a patch for review to netdev@vger.kernel.org :-)