F18 up to F20 -- how?

[Adam Williamson]

On Sun, 2013-12-01 at 19:44 +0000, Beartooth wrote:
> 	I have several machines running F18, which I would like to change 
> to F20 by some sort of upgrade, rather than a fresh install. Can anyone 
> yet guess whether upgrading from a DVD, or using fedup, or yum, or some 
> other way is most likely to succeed with the least trouble?
> 
> 	Among other possibilities, is an upgrade via DVD from F18 to F20 
> Beta, followed by yum updates at regular short intervals, any more or 
> less promising that fedup? (I've had very mixed experience with that.)
> 
> 	Btw, this seems to me much more of a question for the regular 
> Fedora list; but I tried it there, and a couple of people have referred 
> me here.
> -- 
> Beartooth Staffwright, Neo-Redneck Not Quite Clueless Power User
> Remember I have precious (very precious!) little idea where up is.

You got various replies, but to clear up one point, you can't really
upgrade 'via DVD' from F18 to anything, at least not in the way I think
you're thinking about.

The only 'officially recommended' upgrade method from F18 onwards is
fedup. The installer's upgrade mode does not exist any more. fedup is
essentially just a fairly thin wrapper around a 'yum update' which is
performed in a special systemd target. You can feed it packages from a
repository or from a DVD ISO, but it basically does the same thing
either way (you'll have more, and newer, packages available if you use
the repo approach).

Upgrading via yum directly is not 'officially recommended', but lots of
people do it and it often works fine. The only reason we don't
'recommend' it, really, is that it is a proven fact that there are
upgrade scenarios yum simply cannot possibly handle cleanly - certain
things have to be handled outside the packaging system - but in practice
those situations rarely arise. fedup provides us with the potential to
do changes during an upgrade outside of the packaging process, but in
practice we rarely have to actually use that. The last change like that
was the /usr move, in Fedora 17; if you yum'ed to 17 you had to do some
manual labour to make that work, whereas for the 'official' upgrade
processes (anaconda and preupgrade, at the time) we could do it for you.
For all releases since then, a yum upgrade is probably close to as
likely as fedup to work well in practice. It would be 'best practice' to
do it from a console with as few processes and services as possible
running, and it's always a good idea to read and follow
https://fedoraproject.org/wiki/Upgrading_Fedora_using_yum .

I don't know if there's any hard evidence as to whether it's better to
do an 'incremental upgrade' (18->19->20) or a direct one (18->20), to be
honest. I'm sure you can find anecdotal evidence for either. FWIW, I'd
usually go with the direct approach.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Twitter: AdamW_Fedora | XMPP: adamw AT happyassassin . net
http://www.happyassassin.net