Kickstart upgrade to RHEL/CentOS 6.5
 

There is some reason for me to use kickstart with pre-prepared ISO instead of running automated upgrade (i.e., "yum update"), and there is an error message ("upgrade root not found") I'm getting when doing this.

I'm using the same kickstart configuration file as for clear installation, just with "upgrade" instruction instead of "install".

I've found in the Internet solution/workaround for the case when /var is located on a separate partition. Since it's not so in my configuration, the solution is not relevant.

Are there any possibility to upgrade CentOS to 6.5 with kickstart?

It would be simpler to mount the cd/dvd then add it as a yum repo and perform a 'yum update', can you please provide the reason why this is not possible?

Thanks for your answer!
Yes, it's possible. I should also temporary remove the default repos, because the purpose is to control the set of the packages being updated.
The main reason I'm playing with kickstart is that boss prefers this way. Also, I'm wondering why a documented feature does not work, and if I am the only one trying to use it.