rhel68-to-cent68.sh

#!/bin/bash
# rhel68-to-cent68.sh
# This script converts a RHEL 6.8 install into CentOS 6.8
#   Copyright (C) 2016  Jun Go

    # This program is free software: you can redistribute it and/or modify
    # it under the terms of the GNU General Public License as published by
    # the Free Software Foundation, either version 3 of the License, or
    # (at your option) any later version.

    # This program is distributed in the hope that it will be useful,
    # but WITHOUT ANY WARRANTY; without even the implied warranty of
    # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    # GNU General Public License for more details.

    # You should have received a copy of the GNU General Public License
    # along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Jun Go gojun077@gmail.com
# Last Updated 2016-08-04
# This script must be executed as root

# USAGE:
# ./rhel68-to-cent68.sh [mountpt for CentOS 6.8 iso]
# ex: ./rhel68-to-cent68.sh /media
# no trailing slash in the path!

if [ -z "$1" ]; then
  echo "You must specify the path to the CentOS 6.8 iso mountpoint"
  exit 1
fi

yum clean all

if grep --silent "Red Hat" /etc/redhat-release; then
  cp /etc/redhat-release /etc/redhat-release.old
fi

DELETE=(rhnlib
        redhat-release-server-6Server-6.8.0.5.el6.x86_64
        redhat-indexhtml
        plymouth-0.8.3-27.el6_5.1.x86_64
        plymouth-scripts-0.8.3-27.el6_5.1.x86_64
        plymouth-core-libs-0.8.3-27.el6_5.1.x86_64
        dracut-004-409.el6.noarch
        dracut-kernel-004-409.el6.noarch
       )

for i in ${DELETE[*]}; do
  if rpm -q "$i" > /dev/null; then
    echo -e "### Now deleting $i ###\n"
    rpm -e --nodeps "$i"
  fi
done

# Remove RHEL subscription info
subscription-manager clean
yum remove -y subscription-manager rhn-client-tools


if grep --silent "CentOS-6.8" "$1"/RELEASE-NOTES-en-US.html; then
  cd "$1"/Packages || exit 1
  echo -e "### Force updating packages with rpm -Uvh --force ###"
  rpm -Uvh --force centos-release-6-8.el6.centos.12.3.x86_64.rpm \
      centos-indexhtml-6-2.el6.centos.noarch.rpm \
      yum-3.2.29-73.el6.centos.noarch.rpm \
      yum-plugin-fastestmirror-1.1.30-37.el6.noarch.rpm

  # Rename CentOS online .repo files so they won't be used
  echo -e "### Rename CentOS Repo files ###"
  find /etc/yum.repos.d/ -type f -name "CentOS*" -exec mv {} {}.old \;

  # check for local.repo file and create it if it doesn't
  # exist
  if [ -f /etc/yum.repos.d/local.repo ]; then
    echo -e "### Local yum repo file exists ###\n"
    echo -e "### Changing baseurl for local.repo (to CentOS DVD iso) ###\n"
    # Check if the existing local.repo uses mountpoint '/media/Server'
    if grep --silent "/media/Server" /etc/yum.repos.d/local.repo; then
      # change file path to CentOS path
      sed -i "s%file:///media/Server%file://$1%g" \
          /etc/yum.repos.d/local.repo
    fi
  else
     cat << XYZ > /etc/yum.repos.d/local.repo
[CentOS]
name=CentOS
baseurl=file://\$1
enabled=1
gpgkey=file://\$1/RPM-GPG-KEY-CentOS-6

XYZ
  fi

  yum clean all
  yum update -y
  yum install -y plymouth-0.8.3-27.el6.centos.1.x86_64.rpm \
    plymouth-core-libs-0.8.3-27.el6.centos.1.x86_64.rpm \
    plymouth-graphics-libs-0.8.3-27.el6.centos.1.x86_64.rpm \
    plymouth-scripts-0.8.3-27.el6.centos.1.x86_64.rpm \
    dracut-004-409.el6.noarch.rpm \
    dracut-kernel-004-409.el6.noarch.rpm
    #dracut-fips-004-409.el6.noarch.rpm \
    #dracut-network-004-409.el6.noarch.rpm
else
  echo -e "Please mount the proper ISO file\n" 1>&2
  exit 1
fi

# Edit grub.conf to remove references to RHEL
sed -i "s:Red Hat Enterprise Linux 6:CentOS release 6.8:g" /boot/grub/grub.conf
# Edit grub.conf to remove references to RHEL errata kernel
sed -i "s:Red Hat Enterprise Linux Server:CentOS errata:g" /boot/grub/grub.conf

# specify that plymouth boot use VESA framebuffer
#sed -i "s:rhgb quiet:rhgb quiet vga=0x317:g" /boot/grub/grub.conf

echo -e "### Rebuilding initrd to remove RHEL text ###"
# Disable the RHEL text mode boot bar by rebuilding initramd
plymouth-set-default-theme -R details