I tried to upgrade fedora 16 x86-64 via preupgrade a few days ago.
After the first stage up to download of packages and installation of
grub2 for the actual install process ... it went fine.
The new grub2 entry was not bootable (known bug?), but anyway I
modified it manually and started anaconda.
The installer invariably crashed after ?wanting a network connection?
(actually the machine connects manually to the Internet).
All of the tricks including
deletion of /etc/anaconda.repo and modification of the ks file did not work.
Fresh Install from dvd was ok... except for no support for encrypted btrfs.
Grub2 of Kubuntu-12.04 cannot handle Fedora-17 entries at all.
Best
A. Mani
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A. Mani
CU, ASL, CLC,? AMS, CMS
http://www.logicamani.co.cc