I was using Fedora 15 32 bit for a long time but i felt the need to install a 64 bit edition for some memory limitations in the system. Therefore I downloaded the Fedora 16 x86_64 iso file from https://fedoraproject.org/ . The main concern was to install the new system with minimum mess and reconfiguration. I have separate root and /home partitions so there is no problem in the home directory restoration.
The main problem was to install the packages which i had manually installed with yum after i installed the distro. This is a common problem when upgrading to another distro, and it is worse in Microsoft Windows, as all the applications needs to be downloaded from the corresponding third party sites, and to restore either you need to surf through those sites, or keep the installations in your disk.
Export Package List
I didn’t have track what i have installed after except what i have installed at the time of installation from the DVD. There should be an easy way to do this.
The plan which came into my mind is to simply export the installed package list in a text file and then feed this list to yum after i install the new version of the OS. Therefore i started piping yum and cut commands. The first one was like this:
yum list installed | tail -n+3 | cut -d' ' -f1 | cut -d'.' -f1 | tr '\n' ' ' > yum_update_pack_list
The “yum_update_pack_list” file then could be used with yum to install the package.
To confirm that this will not rise any other issues i asked this question in http://ask.fedoraproject.org and was confirmed that it would not be a bad idea. Someone (Remi) provided with an even better installed package list extraction command. It is like as follows:
rpm -qa --qf "%{NAME}\n" > yum_update_package_list
This will list all the packages installed in the system and only print the package names (not the versions) in each line. Check man rpm for details about the options.
Install Fedora and Setup Repositories
The next step was to install Fedora 16. After setting up the internet the first task is to install the repositories which which i had setup in the older installation. I had only rpmfusion repositories, which i setup by pasting the commands from http://rpmfusion.org/Configuration/ page.
Execute yum
Next, simply fed the list to yum :
yum install $(cat yum_update_package_list)
That’s it. The packages will be listed to be installed.
At the time of composing this post, the updates are still running. For those apps which i have installed from source or installed from some other rpm packages (noarch only) which are not available from the configured repositories are in my Downloads directory which i can easily install.
Although i have done this on Fedora, but this is applicable for any rpm based distro and also with the equivalent command sequence with any other Linux distros too. Is there any easier way to achieve this?
Phoxis 
great post