Migrate CentOS 8 to Oracle Linux with the centos2ol.sh Script

Oracle Linux is a RHEL‑compatible distribution that can replace CentOS 8. This guide shows how to migrate an existing CentOS 8 system to Oracle Linux using the official centos2ol.sh script.

Prerequisites

System is running CentOS 8 Minimal. Verify OS version and kernel:

# cat /etc/os-release
NAME="CentOS Linux"
VERSION="8 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="8"
PRETTY_NAME="CentOS Linux 8 (Core)"

# uname -r
4.18.0-240.15.1.el8_3.x86_64

Download and prepare the migration script

Download the script from Oracle's GitHub repository and make it executable:

# wget https://raw.githubusercontent.com/oracle/centos2ol/main/centos2ol.sh
# chmod +x centos2ol.sh

Run the migration

Execute the script to replace installed packages with their Oracle Linux equivalents and update the boot loader:

# ./centos2ol.sh

When the script finishes, reboot the machine:

# reboot

During boot, GRUB now shows two new entries: one for the standard Linux kernel and one for the Unbreakable Enterprise Kernel (UEK).

Verify the new system

Check the OS release file and kernel version to confirm the migration:

# cat /etc/os-release
NAME="Oracle Linux Server"
VERSION="8.4"
ID="ol"
ID_LIKE="fedora"
VERSION_ID="8.4"
PRETTY_NAME="Oracle Linux Server 8.4"

# uname -r
5.4.17-2102.202.5.el8uek.x86_64

The system now runs Oracle Linux Server 8.4 with the UEK kernel, providing a stable, performance‑focused replacement for CentOS 8.