[CentOS] RHEL4 to CentOS 4

Thu Aug 3 14:15:31 UTC 2006
Will McDonald <wmcdonald at gmail.com>

On 03/08/06, tagarsi, arun <atagarsi at cgg.com> wrote:
> Hi ,
>       For reasons I will not go in to does anyone know if you can convert a
> RedHat RHEL4 box to CentOS 4 ? I am hoping this possible with our re
> installing . If it if what do I need to do to get the system to run yum
> instead of the RedHat updates.

It should be relatively simple but test on non-critical,
non-production systems first, obviously.

The old instructions (we Kickstart CentOS on all new systems now) I
have for switching from Whitebox to CentOS, which should be near as
damnit what's needed to switch from RHEL too, were as follows...

rpm --import http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-4
rpm -Uvh http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/initscripts-7.93.20.EL-1.centos4.i386.rpm
\
    http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/diskdumputils-1.1.9-4.i386.rpm
rpm -Uvh http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/centos-release-4-2.1.i386.rpm
rpm -e yum
rpm -Uvh http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/centos-yumconf-4-4.3.noarch.rpm
rpm -Uvh http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/yum-2.4.0-1.centos4.noarch.rpm
\
  http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/python-elementtree-1.2.6-4.i386.rpm
\
  http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/python-sqlite-1.1.6-1.i386.rpm
\
  http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/python-urlgrabber-2.9.6-2.noarch.rpm
\
  http://www.sunsite.org.uk/sites/msync.centos.org/CentOS/4/os/i386/CentOS/RPMS/sqlite-3.2.2-1.i386.rpm

Add this to /etc/yum.repos.d/CentOS-Base.repo

[base]
name=CentOS-$releasever - Base
baseurl=ftp://archive/centos/$releasever/os/$basearch
gpgcheck=1

[update]
name=CentOS-$releasever - Updates
baseurl=ftp://archive/centos/$releasever/updates/$basearch/
gpgcheck=1

[extras]
name=CentOS-$releasever - Extras
baseurl=http://archive/centos/$releasever/extras/$basearch/
gpgcheck=1
enabled=0


Add this to /etc/yum.repos.d/Dag.repo

[archive-rhel4-dag]
name=RHEL4 Linux $releasever - $basearch - DAG
baseurl=ftp://archive/dag/el4/

Quick Yum update...

yum -y update

Where we have "archive" you'd need to replace that with the path to a
local mirror. And obviously the URLs for the RPM commands could be
changed to somewhere closer with more recent RPMs. But that's an
outline of what you'd need.

There are additional artwork RPMs etc. if you're bothered about boot
time splash screens and the like.

Will.