It was last week when a couple of issues summed up and forced me to think about how to update my working machine from Fedora 16 to Fedora 18.
Basically I had the choice between running a fresh (after a decent backup) install or upgrading from Fedora 16, via 17, to 18.
In general I really prefer doing fresh installs - as you get a clean system and old cruft is removed, but this time I tried to avoid to backup all the little pieces which somehow tangent my work environment.
Those pieces ain't mission critical, it's just that re-creating them is boring.
Long story short - I just went the upgrade path, with doing a fresh install being my fallback solution.
I ran pre-upgrade on the Fedora 16, which initially failed (It got confused by the EFI setup), but this could be fixed by manually adding the grub entry for booting up pre-upgrade.
It took a couple of hours until the upgrade was finished. But everything seemed to work. After trying a couple of applications, I installed fedup and - just waited. It felt a bit longer but also finally succeeded.
I was a bit concerned right after the update, because I was confronted with a dracut rescue shell. But a reboot helped.
It seems that there is a time out for lucks prompt, which drops you to the emergency shell in case you don't enter the password in time.
Now, two days later, everything is still working. Only the kerberos client UI is missing and I had to install realmd.
The thing about this is, that I actually didn't expect this upgrade path to work. I expected more hassles.