On Tue, Feb 25, 2014 at 10:25 AM, Styma, Robert E (Robert) <robert.styma at alcatel-lucent.com> wrote: > I recently built a CentOS 6 system as my main machine at home. > With a bit of help from members of this list, it is now working > better than the machine it replaced (RIP). > The new machine works so well, that I would like to convert some > CentOS 5 machines to CentOS6. > > I did some research on the web and the new install is still considered > the proper way to upgrade CentOS. Same as Fedora and RHEL. > The question becomes, "What makes the Ubuntu developers so > clever that they can do major upgrades through their apt based > update system?" > > There must be some sort of gotcha or tradeoff involved in allowing this. > > Does anyone have any insights on why they can get away with this > while CentOS cannot? First, CentOS does exactly what RHEL does, so this is not really a CentOS question. The tradeoff is that Ubuntu doesn't go to the effort to ensure that for 7+ years you can do updates and not have anything that was previously working break because a change from the update. RHEL/CentOS may not be perfect at this, but breakage is very, very rare because the updates are mostly backported security/bug fixes that don't change behavior. Ubuntu does more frequent updates of the included package versions (even with their LTS version) and if a package changes behavior that is left as your problem. By the time RHEL does it's next major release, you have a many-year jump in the underlying package versions with enough changes that even if you could do an automated update it would probably be a bad idea (there may be things as drastic as new filesytem choices, etc.). A fresh install of CentOS isn't difficult and you should have a plan to backup/restore your own data anyway, so once you get used to the timing it works out pretty well to match up major releases with replacing hardware and/or general cleaning up of your own applications and data. -- Les Mikesell lesmikesell at gmail.com