In this article, you will learn how to migrate your CentOS Linux to Red Hat Enterprise Linux (RHEL) 8 operating system.
Table of Contents:
Problem Definition:
Due to the demise of CentOS Linux 8, the system administrators are now looking for alternatives to migrate your existing CentOS Linux server machines.
We have already published a list of CentOS Linux 8 alternatives and also wrote an article on migration of CentOS Linux to CentOS Stream operating system.
Now, we are showing the steps to migrate a existing CentOS Linux server to Red Hat Enterprise Linux (RHEL) operating system. Because Red Hat is now offering free one year subscription for upto 16 servers. Therefore, you can migrate to RHEL 8 and enable the official yum repositories by registering your Linux server with Red Hat subscription manager.
Update Existing Linux Server:
Use a ssh client and login to your CentOS Linux server as root user.
Check the current Linux Kernel and operating system versions.
# uname -r 4.18.0-240.1.1.el8_3.x86_64 # cat /etc/redhat-release CentOS Linux release 8.3.2011
We recommend that you should use Convert2RHEL utility for this migration process. Convert2RHEL is simple tool that can convert your existing CentOS Linux or Oracle Linux operating systems to Red Hat Enterprise Linux (RHEL) 8.
Currently, Convert2RHEL supports migration from CentOS/Oracle Linux 6,7,8 to RHEL 8.
Based on the version of your Linux distro, you can download and install the supported package of Convert2RHEL software. The download URLs are available at Convert2RHEL GitHub page.
Since, we are using CentOS Linux 8 in this article, therefore we are installing the respective Convert2RHEL package by using dnf command.
# dnf install -y https://github.com/oamg/convert2rhel/releases/download/v0.17/convert2rhel-0.17-1.el8.noarch.rpm
Convert2RHEL is written in Python, therefore it also installs Python programming language support herewith.
Update your CentOS Linux software packages to the latest stable versions by using dnf command.
# dnf update -y
After update, check the Linux kernel and operating system versions again.
# uname -r 4.18.0-240.1.1.el8_3.x86_64 # cat /etc/redhat-release CentOS Linux release 8.3.2011
Reboot your Linux server with the updated Kernel.
# reboot
Migrate to RHEL 8 Operating System:
After reboot, login as root user and start the migration process by using the Convert2RHEL utility. You will need your Red Hat login credentials to register your Linux server after migration to RHEL 8.
# convert2rhel --username centlinux
First of all convert2rhel is obtaining a confirmation from user to execute the script.
Some software packages will be removed by the script, and it is asking for the confirmation.
Choose your preferred Red Hat Subscription from the list.
Some more software packages will be removed by the convert2rhel script.
The script is patching the yum configuration file.
Finally, convert2rhel script has been completed successfully.
After successful execution of Convert2RHEL utility, you need to restart your Linux server to boot your operating system with the new RHEL 8 Kernel.
# reboot
After reboot, check the Linux kernel and operating system versions.
# uname -r 4.18.0-240.15.1.el8_3.x86_64 # cat /etc/redhat-release Red Hat Enterprise Linux release 8.3 (Ootpa)
Your CentOS Linux server has been migrated to RHEL 8.
Change the hostname of your Linux server, if required.
# hostnamectl set-hostname rhel-8.centlinux.com
If you faced difficulty in understanding the above article, we recommend that you should buy and read RHCSA Red Hat Enterprise Linux 8 (UPDATED): Training and Exam Preparation Guide (EX200), Second Edition (PAID LINK) by Asghar Ghori.
Conclusion:
In this article, you have migrated your CentOS Linux server to Red Hat Enterprise Linux (RHEL) 8 operating system.