F15 preupgrade: lots of uneraseable dupes

[Bruno Wolff III]

On Mon, Oct 10, 2011 at 13:19:10 -0700,
  JD <jd1008 at gmail.com> wrote:
> On 10/10/2011 01:11 PM, suvayu ali wrote:
> Well, if packages not present in a previous release,
> should not the new packages that replace them be
> marked as "obsoletes <package name>" ?

If something replaces it. However people make mistakes and this doesn't
always get done correctly.

> Or if they are not even replaced by a new package,
> should yum just throw up it's hands and exit with
> error?

It's not clear what should happen with orphaned packages that aren't
obsoleted. While one my want to get rid of any that are blocking updates
of other stuff, one may not want to get rid of all of them. yum distro-sync
can handle this in some cases, but in some complicated cases it can't.

> As I explained my current installation of f14, I also
> make use rpmfusion and atrpms repos, which which
> I disable during upgrade to avoid complications.
> Perhaps that is indeed a source/cause of the failure.

Probably you want to switch to the repos for these at the same time.
Otherwise you are going to have packages from these repos blocking updates
from the Fedora repos.