On Wed, 2015-03-18 at 20:27 -0700, Yasha Karant wrote:
> I have been told that SUSE Enterprise Linux (SLES) supports, without 
> problems or issues, an upgrade in place to migrate from major release N 
> to N+1 without reformatting those parts of the disk / file system that 
> contain systems files (e.g., /usr ,  /boot , etc.).  My understanding is 
> that this is not possible/safe with EL -- e.g., SL6 to SL7.  Does anyone 
> know if this is true -- and works?  If so, why does EL not support the 
> same method?
> 
> Yasha Karant

Hi,

This info is from CentOS but explains some of it.

http://wiki.centos.org/TipsAndTricks/CentOSUpgradeTool

A server upgrade (no desktop) maybe possible, but a desktop version is
not possible due to some packages being of higher versions in 6 than 7
e.g. mesa.

Regards

Phil

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