upgrade Fedora 14 to Fedora 15

Since Fedora 15 was released for some time already, I upgraded my development server from Fedora 14 to Fedora 15 recently. Below is the command set I used to upgrade to Fedora 15. Before run those commands, I backup my virtual machine files in case.

# change account to Root account
[yyjia@jiaFedora14 ~]$ su
Password: 

# upgrade to latest rpm version
[root@jiaFedora14 yyjia]# yum upgrade rpm
Loaded plugins: langpacks, presto, refresh-packagekit
Adding en_US to language list
Zend                                       |  951 B     00:00     
Zend_noarch                                |  951 B     00:00     
fedora/metalink                            |  21 kB     00:00     
jenkins                                    |  951 B     00:00     
jenkins/primary                            | 1.3 kB     00:00     
jenkins                                                                     1/1
updates/metalink                           |  13 kB     00:00     
updates                                    | 4.7 kB     00:00     
updates/primary_db                         | 6.5 MB     00:07     
Setting up Upgrade Process
No Packages marked for Update
[root@jiaFedora14 yyjia]# 

#make sure I have latest packages installed.
[root@jiaFedora14 yyjia]# yum -y update

#clean up yum cache.
[root@jiaFedora14 yyjia]# yum clean all

#insall preupgrade package.
[root@jiaFedora14 yyjia]# yum install preupgrade

#running preupgrade
[root@jiaFedora14 yyjia]# preupgrade

After running preupgrade, we have below screen. I don't want to try Fedora 16 beta version. So, I selected Fedora 15.

I followed instructions shown on the screen. Then, I have a below screen to ask for reboot.

After reboot, the upgrade process starts.

Here is upgrade manual from Fedora web site: http://fedoraproject.org/wiki/YumUpgradeFaq