"In Fedora, the supported method for upgrading from one
release to the next is by downloading the media and rebooting from
the media and using Anaconda. Why was this the case, and what's
wrong with a yum upgrade?
"Seth Vidal: Anaconda has the advantage of
running outside of the system it is upgrading. This means it can do
certain tricks in the event of big changes. The lvm->lvm2
migration, for example. Yum can't do this. Changing the partition
or fs type on a running partition is a bad idea :)
"Will Woods: Another good example: In Fedora 9
we have (experimental) ext4 support, and Anaconda is capable of
migrating your ext3 filesystems to ext4 automatically. But yum
upgrades can't handle this..."