[Centos] Re: Upgrade install using CentOS-3.1 ISO images (Bart Schaefer)

[R P Herrold]

On Sun, 11 Apr 2004 cody at telnet.org wrote:

> It is my understanding that there is no upgrade path available from Red 
> Hat 9 to Red Hat Enterprise Linux 3, so I doubt you will find anything of 
> that nature in the CentOS installer either.

The CentOS installer is simply a straight rebuild (with all
appropiate trademark changed applied) of the RH supplied
anaconda installer, without extension to support upgrades (as
RH did not have that support present in their version)

Intentionally, there is no separate CentOS installer; the 
'yum' upgrade method (which honors dependencies, and will 
remove obsoleted packages) will work, with some intervension, 
as indicated in my prior post.

The cAos project installer, 'cinch', could probably be adapted 
to do installations of CentOS, but it is not clear spending 
the release engineering effort to do so has sufficient demand 
to warrant the effort.  That said, of someone wants to take a 
run at doing so, I am certain we can find a place for a stable 
maintainable effort in the mirror tree.  ;)
 
> It does seem a little odd since RH9 is so compatible with RHEL3.  You 
> should be able to find more information at redhat.com.

The Taroon, and some other RH mailing lists have discussed 
this; some of the transition paths for an upgrade from RHL to 
RHEL are untested; anaconda does upgrades (and installs) 
essentially with RPM in a --force --nodeps mode, and so (as 
it is working from a closed universe of packages) RPM can 
assume that the packageset is consistent and complete

By not directly supporting the RHL to RHEl path, Red hat has 
avoided the need to do much release engineering.  A win for 
them, and probably economically rational.

-- Russ Herrold