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Rocky Linux vs. AlmaLinux: Which is better?
Rocky Linux and AlmaLinux are RHEL-compatible distributions created after Red Hat announced the discontinuation of CentOS in 2020. Although similar, they differ in some approaches.
Red Hat's replacement of CentOS with CentOS Stream has upset companies that depend on Linux as their server OS.
CentOS Stream is a rolling release OS, which means it isn't ideal from a reliability standpoint as it does not have a fixed update release schedule. However, shortly after Red Hat declared the discontinuation of CentOS, two similar distributions were announced: Rocky Linux and AlmaLinux. These two distributions have become popular among CentOS users.
Rocky Linux and AlmaLinux have similar uses and support the same architectures. However, Rocky Linux is a 1-to-1 binary to RHEL, while AlmaLinux is application binary interface (ABI)-compatible with RHEL. Both distributions also have a difference in funding. Compare these newer distributions to decide which OS is best for your company.
Plans to overcome the RHEL source limitation
IBM acquired Red Hat in 2019. In June 2023, Red Hat/IBM decided to make the source for RHEL private, which makes it a challenge for Rocky Linux and AlmaLinux to remain 1-to-1 compatible with RHEL. To this end, both distributions have taken different paths.
Rocky Linux's path
Gregory Kurtzer is the creator of CentOS and Rocky Linux. Starting with CentOS, Kurtzer's goal was to create a free Linux distribution that is 1-to-1 binary-compatible with RHEL. He created Rocky Linux to pick up where CentOS left off.
Rocky Linux has opted to retain the 1-to-1 compatibility through public cloud instances and Universal Base Images based on RHEL.
AlmaLinux's path
AlmaLinux is a product of CloudLinux. AlmaLinux is community-driven and focused primarily as an enterprise-grade Linux distribution. Like Rocky Linux, the goal of AlmaLinux was to remain 1-to-1 binary-compatible with RHEL.
However, AlmaLinux has opted to drop its goal of remaining 1-to-1 binary-compatible with RHEL and instead aims to be ABI-compatible with RHEL. To accomplish this, AlmaLinux plans to use CentOS Stream source code that Red Hat continues to make available.
The similarities between Rocky Linux and AlmaLinux
On the surface, Rocky Linux and AlmaLinux are similar. Their lifecycle and support last up to 10 years. They are designed as production-grade, enterprise OSes and are updated regularly, with a one-business-day lag behind RHEL.
Both distributions use RPM Package Manager and the Dandified YUM package manager. Managing applications in Rocky Linux or AlmaLinux is similar to RHEL. These distributions also use firewalld, iptables and Security-Enhanced Linux (SELinux) as their primary security mechanisms.
Rocky Linux and AlmaLinux both support the same architectures: x86_64, aarch64, ppc64le and s390x.
Both distributions include the following repositories, enabled by default:
- BaseOS. The core set of software packages for functionality.
- AppStream. Additional user space applications, runtime languages and databases.
- Extras. Packages that are not available in RHEL.
For installations with a GUI, Rocky Linux and AlmaLinux default to GNOME.
AlmaLinux and Rocky Linux share similar uses. Both work for enterprise-grade servers, such as web and database servers. They are also similar to container and cloud deployments. Rocky Linux and AlmaLinux are suited to take on any RHEL use case.
The key differences between Rocky Linux and AlmaLinux
The differences between Rocky Linux and AlmaLinux aren't easy to spot, which is a product of both distributions being based on RHEL.
Security
Security approaches differ, although both distributions include Secure Boot and SELinux as security utilities.
AlmaLinux utilizes Center for Internet Security Benchmarks with CIS Configuration Assessment Tool and Open Security Content Automation Protocol. These utilities enable AlmaLinux users to have more flexibility with system security configurations.
Rocky Linux utilizes Network Time Security, focusing on real-time network traffic to identify potential threats.
Funding
AlmaLinux is driven by a nonprofit. CloudLinux and other sponsors, like WebPros and Black Host, grant AlmaLinux a $1 million annual sponsorship to guarantee the distribution will continue and always be free. CloudLinux has been around since 2009. This set amount of funding per year and the longevity of CloudLinux assure users that AlmaLinux will always have funding for updates.
Rocky Linux is community-driven. Ctrl IQ (CIQ), the founding sponsor and service provider of Rocky Linux, has provided $26 million in funds to the distribution. This is a one-time fund, which means more funds will be needed in the future. CIQ was founded in 2020. Prospects of Rocky Linux might be deterred from the distribution if they do not want to take a chance with a newer company sponsoring it.
However, that is not to discount Rocky Linux. CIQ might be a newcomer, but it has grown fast and has an outstanding reputation within the world of technology. Kurtzer has a massive built-in fan base because of CentOS, so the Rocky Linux community should continue to grow. With Kurtzer's dedication to improving what he did with CentOS, users can be sure he is committed to the community.
Popularity
According to Google Trends, Rocky Linux has been the most popular choice since November 2020. The trend continues as Rocky Linux sees more interest over time and a larger subregion breakdown within the U.S. On a worldwide scale, the difference is less dramatic -- although Rocky Linux still leads. Another metric report focused on usage and showed a more accurate listing of how each RHEL-based OS trends.
AlmaLinux and Rocky Linux serve as proper replacements for CentOS or RHEL. Download and install both to determine which is best for you.
Jack Wallen is an award-winning writer and avid promoter/user of the Linux OS.
