On Thu, Jul 25, 2013 at 1:28 AM, David G.Miller <[log in to unmask]> wrote:

> The problem of upgrading from FC-n to FC-n+1 is basically the same as
> upgrading EL-n to EL-n+1.  There tends to be more of them and that means

There are big advantages to updating Fedora. compared to EL. The big
one is that Fedora comes out far, far  more frequently, so the jump in
core libraries and components is much smaller.

> working out things like dependencies and obsolete packages is even uglier.
> You also run into TUV wants an installation of EL that is rock solid.  If an
> upgraded FC system is unstable, that's almost to be expected.  If an
> upgraded EL system is unstable, TUV gets bad press.

And loses engineering time straightening out the mess on support
contracts, especially if the client can say "you published this
patch", and the resulting "always mount a scartch monkey?"
(http://edp.org/monkey.htm)

> I'm guessing you could back-port FedUp to EL and have a reasonable shot at
> upgrading EL-n to EL-n+1.  I wouldn't want to guarantee that an arbitrarily
> complex installation will work though and the people who really want to
> upgrade are those with really complex systems that they don't want to have
> to re-create from a clean installation.  So we end up stuck with the
> contradiction that simple installations could probably be upgraded but the
> complex installations that people really want to upgrade can't.

It's also a good chance to clean up from whatever genius procedures
the previous systems personnel did, unaware of configuration conflicts
that no RPM installer or normal software might predict. Hard-coded
uid's for RPM installer scripts, for example, may overlap and conflict
with older software that simply is not designed to have its admin
account uid and gid reset.