Upgrade Fedora 19 -> Fedora 20 Heisenbug

Yersterday I attemtped to upgrade my Fedora 19 installation.

The usual way with fedup started fine.

fedup-cli --network 20 --reboot

The packages were downloaded and the reboot-entry in grub was installed.

After downloading several times and rebooting the update installation in the
rebooted system was not started. After every reboot the GNOME desktop
should be started.

Even disabling the desktop and removing the nvidia drivers didn't work.  I need them, because I use also an external monitor for extending the display.

After some attempts, I found an update instruction with yum here.

The instructions are:

# rpm --import https://fedoraproject.org/static/246110C1.txt
# yum update yum
# yum --releasever=20 distro-sync

After some hours and a reboot:
[ewer@lxewer ~]$ cat /etc/fedora-release
Fedora release 20 (Heisenbug)

The system with the new Fedora 20 ( Heisenbug) is up and running