Hi all !

I am new to SL... I am a RedHat user since redhat 5 (the old red hat, 
not rhel5). I had several server running Tao Linux when it was 
discontinued. I then used CentOS to run my servers. I am happy with 
those for the moment.

We have deployed over the past several month a cluster of 8 nodes 
running RHEL6 (paid subscriptions), and a backup cluster of 8 nodes is 
on the way. Now that I needed some EL6 servers for testing and for 
routers and other purposes, I successfully transformed 3 of my servers 
from an unsubscribed RHEL6 to SL6, and updated them successfully.

Now, I have a question, there are some CentOS 5 servers that I wish to 
update to SL6. So, I can switch those to SL5, and do an upgrade via the 
DVD. I would rather do an upgrade rather than a full install.
Does sunc a process can be done ?