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AlmaLinux Review: a CentOS Clone Supported by CloudLinux

Written by Mantas Levinas
on June 07, 2021

What is AlmaLinux?

AlmaLinux is an open-source Linux distribution focused on long-term stability, that is a 1:1 binary compatible fork of Red Hat Enterprise Linux (RHEL). It is designed to fill the gap left by the demise of the CentOS stable release.

AlmaLinux is a forever-free operating system that is planned to match every RHEL release. CloudLinux has promised to invest $1M annually into the maintenance of AlmaLinux, as well as additional funding and support from companies like arm, Equinix, cPanel and the like.

AlmaLinux vs CentOS

So, what happened with CentOS and why AlmaLinux was created?

When Red Hat announced that CentOS 8 will stop being supported by the end of 2021, many felt betrayed. Starting from 2022 the only supported version of CentOS is going to be CentOS Stream. A story of a stable community-driven enterprise-grade Linux distribution seemed to come to an end.

Ever since CentOS was created it has been a downstream version of RHEL, and there was a stable feature release pipeline.

The latest bleeding-edge technology was first introduced in Fedora Linux, it then went through Red Hat’s internal processes, and, if approved, was released in RHEL. CentOS was simply a 1:1 build of RHEL minus its proprietary logos and priority support.

Image 1 - an old downstream pipeline of CentOS

Starting with 2022 CentOS project shifts focus to CentOS Stream. From then on, new features will be first introduced in CentOS Stream, and later be incorporated into RHEL. CentOS Stream will become an upstream (development) branch of RHEL.


Image 2 - a new upstream pipeline of CentOS

This is where AlmaLinux comes into play by offering a downstream 1:1 build of RHEL, just like the original CentOS was intended to do.

What’s inside AlmaLinux 8.3?

AlmaLinux is ‘bug-to-bug‘ compatible with RHEL and has identical software as its corresponding RHEL version. For instance, AlmaLinux 8.3 is the first AlmaLinux release, and the version number is a reflection of the RHEL version it is based on, more specifically, RHEL 8.3.

Every piese of software that is available on RHEL 8.3 is also available on AlmaLinux 8.3.

How to switch from CentOS to AlmaLinux?

AlmaLinux ensures effortless migration from CentOS. Usually migrating from one operating system to another is a tedious and costy process, but with AlmaLinux it‘s a different story. You can bid farewell to your old CentOS ecosystem – whether it‘s a single machine or a swarm of servers – in an instant with zero migration downtime.

AlmaLinux provides you with easy-to-use migration scripts to transition from CentOS. It‘s a minimum investment for your business and requires no existing software changes.

Why should we trust AlmaLinux?

Red Hat‘s decsion to change the roadmap for CentOS 8 support and shift the course of CentOS project has left many dismayed. A bold mission statement and a bunch of promises are no longer enough. Engineers want to see robust safeguards to prevent any major course shifts in the future, and AlmaLinux is trying to establish such.

CloudLinux is investing $1M annually into the maintenance of AlmaLinux to ensure thoroughly tested updates and security patches for AlmaLinux 8.x until 2029. The project is owned and controlled by a non-profit, and the community is involved in every step, including the governing board. It means that the community can push AlmaLinux forward no matter what happens to CloudLinux organization.

To wrap up

AlmaLinux is a forever-free Linux distribution led by a community on a non-profit bases. It‘s intended to be a downstream version of RHEL and continue from where CentOS 8 left off. Hoepfully, AlmaLinux is going to be a trustworthy CentOS replacement and serve the community well for the years to come.