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Updating grub shoud be done AFTER rebooting?
Mrdave said: I had probles launching grub-install /dev/sda just after the upgrade and before rebooting to the new kernel, it resulted in a unbootable system, I had to use the rescue CD and grub-install again.
This happened in F7 > F8 upgrade, in F8 > F9 I did grub-install after reboot and had no problems.
Kiilerix: Strange. I have never seen that. But I have seen that I had to do a grub-install _before_ rebooting. So I don't think there is general advice here. If others have experience in this area please let us know.
Updating from 8 => 9
Yum was not selecting any updates when doing "yum upgrade". I solved this by doing "yum --noplugins upgrade". I think one of the yum plugins was causing a problem.