From Fedora Project Wiki
To check an upgrade path works:
- find a test Fedora system,
- make sure none of the new packages are already installed[1],
- install part or all of the old package set,
- copy the new packages to a local directory[2],
- run createrepo on this directory[3],
- point yum to it[4],
- try a yum update.
- if that fails, try to understand why, rpm -e whatever yum update installed and repeat from step 1.
You can also use:
rpm -qp --obsoletes mypackage
… to check the obsoletes declared by one of your new packages and,
yum list obsoletes
before the yum update to check what yum thinks about your new packages[5].
Notes: