[CentOS] update from 4.8 to 5.4?

Bob wrote:
> At Fri, 4 Jun 2010 15:16:05 -0400 CentOS mailing list <centos at centos.org>
> wrote:
<snip>
>> I'm running CentOS 4.8 and have some DVD's for 5.4. I have a lot of
>> customized and additional software installed and would like to avoid
>> starting over with  a scratch install. After the upgrade from the DVD I
>> would do a yum upgrade to 5.5.
>>
>> Is this a workable (and safe) thing to do? What should I look out for?
>>
>
> What I did was carve out fresh /, /usr, and /var file systems out of my
> VG (I had enough free space) and did a fresh install, using the
> *existing* /boot file system.  I thus created a dual boot system: 4.8 AND
<snip>
> I would recomend *against* trying to do a direct upgrade -- it is too
> likely to leave some cruft behind, which could cause all many of
> problems later on.

It is officially (according to RH, AFAIK) NOT recommended to go up a full
release by update. Subreleases are fine, but you want a clean install for
a new release (that is, 4.x to 5.x).

I recommend what Bob suggested; in fact, I have an article that was
published in SysAdmin magazine a few years ago saying just that. (If you
want to read the article, it's a link at <http://24.5-cent.us>, and it was
called Upgrading Linux).

         mark