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Discover the three major CentOS clones
Free, open source AlmaLinux, Rocky Linux and VzLinux are clones of the popular CentOS Linux distribution, which became a rolling release from IBM Red Hat.
Many businesses used CentOS as a reliable, free and open source Linux distribution that could power many ecosystems -- until IBM Red Hat decided to end CentOS in favor of the rolling release candidate, CentOS Stream. Some admins and companies had no choice but to drop CentOS because common software, such as web hosting software cPanel, no longer worked with CentOS Stream.
Fortunately, several open source clones of CentOS have arisen, all of which are 1:1 binary compatible with Red Hat Enterprise Linux (RHEL). That means any of these clones behave exactly like the original CentOS did.
Several CentOS clone distributions have become popular among Linux admins. Although they all feel and act similarly to CentOS, subtle differences might lead certain data centers to adopt one versus another. AlmaLinux, Rocky Linux and VzLinux represent the three most popular CentOS clones.
AlmaLinux
CloudLinux released AlmaLinux as the first CentOS clone to hit the market. CloudLinux initially made its mark as a hosting provider and also created CloudLinux OS, a Linux distribution for shared hosting environments. CloudLinux also created TuxCare, an enterprise-grade support system for AlmaLinux that keeps AlmaLinux systems updated and secure for years to come.
Vendors such as AWS, Arm, Open Source Lab, cPanel, Chef, Plesk and Mattermost support AlmaLinux. CPanel's support in particular means admins can install both cPanel and WHM on the system, which enables them to automate a variety of web hosting tasks just like they could with CentOS.
CloudLinux offers AlmaLinux as an installable ISO image, but admins can also convert their existing CentOS 8 distribution to AlmaLinux.
Rocky Linux
The creator of CentOS, Gregory Kurtzer, created Rocky Linux as another 1:1 binary compatible RHEL distribution after Red Hat and IBM announced CentOS would become a rolling release.
Just like AlmaLinux, Rocky Linux behaves like CentOS 8 or RHEL 8 and will remain free, open, collaborative and secure. Vendors such as 45Drives, OpenDrives, MontaVista and AWS support Rocky Linux, which means admins can deploy it on cloud-hosted services.
Rocky Linux is a community-supported distribution just like CentOS was in the beginning. Interested admins can install Rocky Linux from an ISO image or convert their existing CentOS 8 distributions.
VzLinux
VzLinux has a data center pedigree centered around OpenVZ. OpenVZ started as Virtuozzo, an OS-level server virtualization platform created by the company of the same name. VzLinux began as a guest OS on the Virtuozzo platform but evolved in such a way that it can now run on nearly any virtualization system.
At this point, instead of having to depend on OpenVZ to run VzLinux, an admin can deploy this CentOS-like operating system on bare metal or any number of cloud-based hosts. VzLinux offers a few unique features, such as CentOS conversion dry runs, snapshot creation and rollback, and unattended mass conversion.
Virtuozzo has announced plans for the future of VzLinux, including new optimized variations of the distribution for containers or virtual machines.
And like both AlmaLinux and Rocky Linux, Virtuozzo claims that VzLinux will remain free and open source forever. Admins can download and install VzLinux from an ISO image.
