Proposed F19 Feature: Fedora Upgrade - using yum

[Bill Nottingham]

Miroslav Suchý (msuchy at redhat.com) said: 
> On 01/23/2013 07:50 PM, Lennart Poettering wrote:
> >The thing is that doing on-line updates only works for stuff you can
> >restart, and that doesn't mind that things are not atomically
> >updated. However, much (most?) of our code isn't like that. Anybody who
> 
> What could not be restarted? And what we can do to fix that?
> 
> If this work for Debian/Ubuntu, why it could not work for Fedora?

Essentially, the idea of a major release is to do the sorts of upgrades
that don't work cleanly on a running system. Examples would be:

- mysql database version upgrade (or similar upgrades that require
  a format conversion)
- switching out the system python interpreter version
- switching from a static /dev to udev
- switching init systems
- switching a script from being sysv to being a systemd service
- refactoring of a systemd service if necessary
- /usr move
- introduction of changes that require a new kernel subsystem mount
  point, or the move of one (/selinux to /sys/fs/selinux, for example)

None of these things are things that will work perfectly reliably in an
on-line upgrade mechanism.

Bill