fedora 20 to 21

[Patrick Dupre]

Hello,

I wish to update a fedora 20 installation to 21 by using a DVD.
Is it possible?
Actually, I burn a DVD bootable server fedora 21, but I did not find
the option update.
When I go to installation
then System, I can select my hard drive and manually partitioning
I can see the installed system (/ /boot and swap)
I can install fedora 21 but not on the same partition (I can reuse /boot)
I have to install it on a new /
I cannot have a mounting point / on the old fedora /
This seems to indicate that I cannot upgrade from this DVD.
How do you update a fedora 20 without network?

Thank.

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 Patrick DUPRÉ                                 | | email: pdupre at gmx.com
 Laboratoire de Physico-Chimie de l'Atmosphère | |
 Université du Littoral-Côte d'Opale           | |
 Tel.  (33)-(0)3 28 23 76 12                   | | Fax: 03 28 65 82 44
 189A, avenue Maurice Schumann                 | | 59140 Dunkerque, France
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