To upgrade or not to upgrade....

[Smith, Herb]

All,

I have just noticed that FC6 is available and the question is how does
the upgrade process work?  More specifically, is there anything that
sets out which directories are not affected by the upgrade process.  I
have a number of applications installed in /opt and other places and
wondered if these would be affected. I admit that I probably haven't
handled that process as well as I could have in all cases, but that is
due to my own lack of understanding sometimes.  I assume that /home will
be unaffected, but it is not clear if the files located in some of these
other locations that are not part of the Fedora distribution will be
disturbed.

Any insight would be helpful.

Thanks in advance,

Herb

[Markku Kolkka]

Smith, Herb kirjoitti viestissään (lähetysaika perjantai, 3. 
marraskuuta 2006 23:54):
> I have a number of 
> applications installed in /opt and other places and wondered
> if these would be affected.

Fedora packages don't install anything in /opt, so it will be 
untouched in an upgrade.

[James Wilkinson]

Markku Kolkka wrote:
> Fedora packages don't install anything in /opt, so it will be 
> untouched in an upgrade.

Unless the files are part of a third-party RPM that is (recorded in the
RPM database as being) dependent on a particular version of a Fedora
Core package. In that case, the upgrade will update the old Fedora Core
package, and try to upgrade the third-party RPMs to a version that *can*
co-exist with the new Core package. If it can't find any upgraded RPMs,
it will remove them, to keep the RPM database consistent.

I don't know what happens if there is a new compat-* version of the old
Core package. I'd like to see it automatically installed to satisfy the
dependencies.

Hope this helps,

James.

[Paul Howarth]

James Wilkinson wrote:
> Markku Kolkka wrote:
> > Fedora packages don't install anything in /opt, so it will be 
> > untouched in an upgrade.
>
> Unless the files are part of a third-party RPM that is (recorded in the
> RPM database as being) dependent on a particular version of a Fedora
> Core package. In that case, the upgrade will update the old Fedora Core
> package, and try to upgrade the third-party RPMs to a version that *can*
> co-exist with the new Core package. If it can't find any upgraded RPMs,
> it will remove them, to keep the RPM database consistent.

Is this behaviour documented somewhere, since I have yet to see it after 
a number of upgrades to FC6? I have yet to see a package removed as part 
of an upgrade if it wasn't explicitly obsoleted by another package.

Paul.

[James Wilkinson]

Markku Kolkka wrote:
> Fedora packages don't install anything in /opt, so it will be untouched
> in an upgrade.

I replied:
> Unless the files are part of a third-party RPM that is (recorded in the
> RPM database as being) dependent on a particular version of a Fedora
> Core package. In that case, the upgrade will update the old Fedora Core
> package, and try to upgrade the third-party RPMs to a version that *can*
> co-exist with the new Core package. If it can't find any upgraded RPMs,
> it will remove them, to keep the RPM database consistent.

Paul Howarth asked:
> Is this behaviour documented somewhere, since I have yet to see it after a 
> number of upgrades to FC6? I have yet to see a package removed as part of an 
> upgrade if it wasn't explicitly obsoleted by another package.

Hmm. That's what I thought happened. I haven't explicitly checked this...

http://fedoraproject.org/wiki/DistributionUpgrades
# The installation overrides any third party packages which conflict with
# the default installation set.
which, to my mind, is not the clearest language.

I'm sure I read something fairly definitive to this effect, but now I
can't find it anywhere. Nor yet can I find any documentary evidence on
the Web one way or another.

I would maintain that Anaconda *ought* to remove packages if there's no
other way to update Core packages, but without trying, I've no idea.

(But that's why responses go to the list, right? So you can catch my
mistakes?)

James.

[Paul Howarth]

James Wilkinson wrote:
> Markku Kolkka wrote:
> > Fedora packages don't install anything in /opt, so it will be untouched
> > in an upgrade.
>
> I replied:
> > Unless the files are part of a third-party RPM that is (recorded in the
> > RPM database as being) dependent on a particular version of a Fedora
> > Core package. In that case, the upgrade will update the old Fedora Core
> > package, and try to upgrade the third-party RPMs to a version that *can*
> > co-exist with the new Core package. If it can't find any upgraded RPMs,
> > it will remove them, to keep the RPM database consistent.
>
> Paul Howarth asked:
> > Is this behaviour documented somewhere, since I have yet to see it after a 
> > number of upgrades to FC6? I have yet to see a package removed as part of an 
> > upgrade if it wasn't explicitly obsoleted by another package.
>
> Hmm. That's what I thought happened. I haven't explicitly checked this...
>
> http://fedoraproject.org/wiki/DistributionUpgrades
> # The installation overrides any third party packages which conflict with
> # the default installation set.
> which, to my mind, is not the clearest language.

I read that as "anaconda will ignore conflicts and dependencies that any 
third party packages may have with the packages being installed", which 
is pretty well how anaconda behaved before the yum backend was brought in.
> I'm sure I read something fairly definitive to this effect, but now I
> can't find it anywhere. Nor yet can I find any documentary evidence on
> the Web one way or another.
>
> I would maintain that Anaconda *ought* to remove packages if there's no
> other way to update Core packages, but without trying, I've no idea.

OOh, I certainly wouldn't like that. There may be proprietary/local 
packages on there that need to be manually upgraded because the vendor 
doesn't provide a repo that can be used at install time. I think it's 
better to leave those in place and findable using "package-cleanup 
--problems" rather than simply removing them so that the sysadmin has to 
figure out what's gone and replace it. Although it might be easy as 
looking in upgrade.log to see what was removed, it would be better not 
to remove packages at all. For example, a package might have a bunch of 
config files that need editing for the target system. Removing the 
package will leave a bunch of .rpmsave files that need to be merged back 
in when the new package is installed, whereas in many cases a manual 
upgrade will not need that effort because the config files won't have 
changed between releases.

Paul.