On 04/24/2011 08:14 PM, Nicolas Ross wrote:
> 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 ?

My default answer is always "Do a fresh install.  You'll thank me 
later."  That's even if you are doing a RHEL5 -> RHEL6.

But, if you are determined, at the DVD boot prompt, hit tab (so that you 
get the boot options) and put "upgradeany" at the end of the line.

You will then be able to follow the upgrade steps.
http://www.scientificlinux.org/distributions/6x/installing/upgrade-guide-full.html

Note1: I have not tried this with CentOS to SL.  But in theory it should 
work.

Note2: Please remember my first statement.  It's much better to just do 
a fresh install that an upgrade.

Troy
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Troy Dawson  [log in to unmask]  (630)840-6468
Fermilab  ComputingDivision/SCF/FEF/SLSMS Group
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