We have successfully updated from Linux fedora 21 to fedora 22, 5 systems now, all without any issues whatsoever. The 6th and final system however had failed, 10 times now.
The upgrade process starts off well with
fedup –network 22
downloading 1800+ packages and completing successfully
The next step is to reboot into the upgrade.
That works.
Welcome to Fedora 21, reached target local file system, mounting drives, reached target system upgrade
Then it reboots back into Fedora 21, too fast to see what error was on the screen.

Time after time this repeated. Logs showed nothing helpful.
In desperation, I videod the screen and watch it frame by frame in playback and came across these errors:

messages:Jun 3 13:38:34 S99 ln: failed to create symbolic link ‘/system-upgrade-root/var/log’: No such file or directory

messages:Jun 3 13:38:34 S99 moving mounts into /system-upgrade-root

messages:Jun 3 13:38:34 S99 mount: /system-upgrade-root is not mountpoint or bad option

messages:Jun 3 13:38:34 S99 mount: mount point /system-upgrade-root/sysroot does not exist

Google searching showed no answers. Permissions look good, the correct symbolic links and folders appear in the root directory. I even added chmod a+w to see if that made a difference. It did not.

lrwxrwxrwx 1 root root 23 Jun 3 13:27 system-upgrade -> /var/lib/system-upgrade
drwxrwxrwx 3 root root 4096 Jun 3 12:30 system-upgrade-root

A few more attempts were made with
fedup -d -v –network 22 (debug, verbose)
but that only showed more info on the initial download of the 1800+ packages.

Then also tried to start from scratch with
fedup-cli –clean
which erased all of the download packages and trying again, still failed the same way.

Also made sure of enough drive space by removing some older kernels. It looks like space is not an issue.

[]$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 50G 9.6G 38G 21% /
/dev/sda6 202G 114G 78G 60% /web
/dev/sda1 477M 189M 259M 43% /boot
/dev/sda5 39G 1.1G 36G 3% /home

So we are at a standstill until we can come across some tip or idea on how to proceed from here.