CentOS vs AlmaLinux: A Comparison

AlmaLinux is a relatively new operating system meant to act as a CentOS replacement. How did AlmaLinux come to be? RedHat, the company that created and maintains RedHat Enterprise Linux (RHEL), announced on December 8th, 2020, that CentOS would be repurposed to CentOS Stream. CentOS Stream now acts as an upstream testing platform where new and updated software will first be deployed and tested before being released to RHEL users. 

CentOS Stream’s shift from a downstream distribution to an upstream one left many users and organizations questioning RHEL’s plans with CentOS. As a result of this shift, several organizations worldwide announced plans to create a CentOS replacement, including:

• AlmaLinux.
• Rocky Linux.
• Oracle Linux.
• Springdale Linux.
• ClearOS Linux.
• Amazon Linux 2.

What is CentOS?

CentOS (Community Enterprise Operating System) is a Linux distribution that provides a free, open-source, community-driven alternative to enterprise operating systems. It is based on the source code of Red Hat Enterprise Linux (RHEL) and aims to provide a stable, reliable, and consistent platform for server environments and other computing needs.

Key features of CentOS include:

1. Stability and Reliability: CentOS is known for its stability and reliability, making it well-suited for production servers and mission-critical applications. It benefits from the rigorous testing and quality assurance processes associated with enterprise-grade operating systems like RHEL.
2. Long-Term Support: CentOS offers long-term support (LTS) releases, which means that each major version receives updates and security patches for an extended period, typically up to 10 years. This allows users to maintain stable environments without the need for frequent upgrades.
3. Compatibility with RHEL: CentOS is binary-compatible with RHEL, meaning that software packages and applications designed for RHEL can usually run on CentOS without modification. This compatibility makes it easier for organizations to transition between the two distributions as needed.
4. Community Support: CentOS benefits from a large and active community of users and contributors who provide support, documentation, and assistance through forums, mailing lists, and other channels. This community-driven model ensures that users have access to resources and help when needed.
5. Security Updates: Like RHEL, CentOS receives regular security updates and patches to address vulnerabilities and protect against security threats. These updates are maintained by the CentOS community and are typically released in a timely manner to ensure the security of the operating system.
6. Variants: CentOS offers several variants tailored to specific use cases, including CentOS Stream, which provides a rolling-release model for developers and enthusiasts; CentOS Atomic Host, optimized for running containerized applications; and CentOS Linux, the traditional CentOS distribution focused on stability and compatibility.

Advantages and Disadvantages of CentOS

CentOS, like any operating system, comes with its own set of advantages and disadvantages. Here’s an overview of both:

Advantages

1. Stability and Reliability: CentOS is renowned for its stability and reliability, making it a preferred choice for production servers and mission-critical applications. It benefits from the extensive testing and quality assurance processes associated with its upstream source, Red Hat Enterprise Linux (RHEL).
2. Long-Term Support: CentOS offers long-term support (LTS) releases, ensuring that each major version receives updates and security patches for an extended period, typically up to 10 years. This allows organizations to maintain stable environments without the need for frequent upgrades.
3. Compatibility with RHEL: CentOS is binary-compatible with RHEL, meaning that software packages and applications designed for RHEL can generally run on CentOS without modification. This compatibility simplifies software deployment and migration between the two distributions.
4. Security Updates: CentOS receives regular security updates and patches to address vulnerabilities and protect against security threats. These updates are maintained by the CentOS community and are typically released promptly to ensure the security of the operating system.
5. Community Support: CentOS benefits from a large and active community of users and contributors who provide support, documentation, and assistance through forums, mailing lists, and other channels. This community-driven model ensures that users have access to resources and help when needed.
6. Variants for Different Use Cases: CentOS offers variants tailored to specific use cases, such as CentOS Stream for developers and enthusiasts seeking a rolling-release model, CentOS Atomic Host optimized for running containerized applications, and CentOS Linux, the traditional CentOS distribution focused on stability and compatibility.

Disadvantages

1. Delayed Updates: While CentOS provides long-term support, updates and new features are typically delayed compared to RHEL. This delay can be a disadvantage for users who require the latest features and technologies for their deployments.
2. Limited Desktop Environment: CentOS is primarily designed for server environments, and while it can be used as a desktop operating system, it may not offer as polished or comprehensive desktop environments as other Linux distributions specifically tailored for desktop use.
3. Software Availability: Although CentOS offers a wide range of software packages through its repositories, some proprietary software and bleeding-edge technologies may not be readily available. Users requiring specific software packages may need to rely on third-party repositories or compile software from source.
4. Enterprise Focus: While CentOS is suitable for many use cases, it may not be the best choice for organizations requiring official support, certifications, or specialized features offered by commercial Linux distributions like RHEL or Ubuntu. Such organizations may prefer the added assurances and services provided by commercial vendors.
5. Community Support Variability: While the CentOS community is generally robust and helpful, the quality and timeliness of support can vary depending on the availability of volunteers and contributors. Users may encounter challenges in finding solutions to niche or complex issues.

What is AlmaLinux?

AlmaLinux is a free, open-source Linux distribution designed to be a drop-in replacement for CentOS. It aims to provide a stable, community-driven alternative to CentOS following the announcement by Red Hat that CentOS Linux would shift its focus from CentOS Linux to CentOS Stream, which caused concerns among users who relied on CentOS for its long-term support and stability.

Key features of AlmaLinux include:

1. Compatibility with RHEL: AlmaLinux is binary-compatible with Red Hat Enterprise Linux (RHEL), which means that software packages and applications designed for RHEL can run on AlmaLinux without modification. This compatibility makes it easy for organizations to migrate from CentOS or RHEL to AlmaLinux.
2. Stability and Long-Term Support: AlmaLinux aims to provide long-term support (LTS) releases with updates and security patches for an extended period, similar to CentOS. This ensures that users can maintain stable environments without the need for frequent upgrades.
3. Community-Driven: Like CentOS, AlmaLinux is driven by a community of users and contributors who provide support, documentation, and assistance through forums, mailing lists, and other channels. This community-driven model ensures that users have access to resources and help when needed.
4. Focus on Stability and Reliability: AlmaLinux places a strong emphasis on stability and reliability, making it suitable for production servers and mission-critical applications. It benefits from the extensive testing and quality assurance processes associated with its upstream source, RHEL.
5. Enterprise-Grade Features: AlmaLinux includes enterprise-grade features such as security updates, performance optimizations, and support for a wide range of hardware architectures. This makes it suitable for a variety of use cases, from small businesses to large enterprises.
6. Ease of Migration: AlmaLinux is designed to be a drop-in replacement for CentOS, making it easy for users to migrate their existing CentOS deployments to AlmaLinux without significant changes or disruptions.

Advantages and Disadvantages of AlmaLinux

As with any operating system, AlmaLinux comes with its own set of advantages and disadvantages. Let’s explore them:

Advantages

1. Compatibility with RHEL: AlmaLinux is binary-compatible with Red Hat Enterprise Linux (RHEL), which means that software packages and applications designed for RHEL can run on AlmaLinux without modification. This compatibility makes it easy for organizations to migrate from CentOS or RHEL to AlmaLinux.
2. Stability and Long-Term Support: AlmaLinux aims to provide long-term support (LTS) releases with updates and security patches for an extended period, similar to CentOS. This ensures that users can maintain stable environments without the need for frequent upgrades.
3. Community-Driven: AlmaLinux is driven by a community of users and contributors who provide support, documentation, and assistance through forums, mailing lists, and other channels. This community-driven model ensures that users have access to resources and help when needed.
4. Focus on Stability and Reliability: AlmaLinux places a strong emphasis on stability and reliability, making it suitable for production servers and mission-critical applications. It benefits from the extensive testing and quality assurance processes associated with its upstream source, RHEL.
5. Enterprise-Grade Features: AlmaLinux includes enterprise-grade features such as security updates, performance optimizations, and support for a wide range of hardware architectures. This makes it suitable for a variety of use cases, from small businesses to large enterprises.
6. Ease of Migration: AlmaLinux is designed to be a drop-in replacement for CentOS, making it easy for users to migrate their existing CentOS deployments to AlmaLinux without significant changes or disruptions.

Disadvantages

1. Limited Desktop Environment: Like CentOS, AlmaLinux is primarily designed for server environments, and while it can be used as a desktop operating system, it may not offer as polished or comprehensive desktop environments as other Linux distributions specifically tailored for desktop use.
2. Software Availability: While AlmaLinux offers a wide range of software packages through its repositories, some proprietary software and bleeding-edge technologies may not be readily available. Users requiring specific software packages may need to rely on third-party repositories or compile software from source.
3. Delayed Updates: Updates and new features in AlmaLinux may be delayed compared to RHEL, as AlmaLinux relies on the upstream source for its packages. This delay can be a disadvantage for users who require the latest features and technologies for their deployments.
4. Commercial Support: While AlmaLinux is community-driven and provides community support, users who require official commercial support, certifications, or specialized features may need to consider commercial Linux distributions like RHEL or seek support from third-party vendors.

Differences Between CentOS vs Alma Linux

entOS and AlmaLinux are both Linux distributions aimed at providing a stable, community-driven alternative to Red Hat Enterprise Linux (RHEL). However, there are some differences between the two distributions:

1. Origin and Background:

• CentOS: CentOS originally started as a community-driven rebuild of RHEL, providing a free, open-source alternative with binary compatibility to RHEL.
• AlmaLinux: AlmaLinux was created specifically as a replacement for CentOS after the announcement of CentOS shifting focus to CentOS Stream. It is also a binary-compatible distribution with RHEL.

2. Governance and Support:

• CentOS: CentOS was previously managed by the CentOS Project, which was governed by the CentOS Governing Board. However, after the changes announced by Red Hat, CentOS shifted its focus to CentOS Stream, which caused concerns among users relying on CentOS for long-term stability.
• AlmaLinux: AlmaLinux is governed by the AlmaLinux OS Foundation, a non-profit organization established to oversee the development and maintenance of AlmaLinux. It aims to provide long-term support and stability as a drop-in replacement for CentOS.

3. Release Schedule:

• CentOS: CentOS had a traditional release model, with major releases followed by point releases that included updates and security patches.
• AlmaLinux: AlmaLinux follows a similar release model, with LTS releases planned to receive updates and support for an extended period, typically up to 10 years.

4. Community and Contributors:

• CentOS: CentOS had a large and active community of users and contributors who provided support, documentation, and assistance.
• AlmaLinux: AlmaLinux also relies on a community-driven model with active participation from users and contributors. However, it was specifically created in response to concerns raised by the CentOS community.

5. Focus and Direction:

• CentOS: CentOS was initially focused on providing a stable, community-driven alternative to RHEL with long-term support and compatibility.
• AlmaLinux: AlmaLinux was created with the specific aim of filling the void left by the changes to CentOS and providing a reliable, drop-in replacement with a strong emphasis on stability, reliability, and long-term support.

6. Branding and Identity:

• CentOS: CentOS had established itself as a popular and trusted distribution for server environments, with a recognizable brand and identity.
• AlmaLinux: AlmaLinux is a relatively newer distribution but has gained traction as a successor to CentOS, inheriting some of the brand recognition and user base from its predecessor.

Conclusion

In the comparison between CentOS and AlmaLinux, both distributions offer stability, community support, and compatibility with Red Hat Enterprise Linux (RHEL). However, AlmaLinux, born in response to concerns over CentOS’s shift in focus, presents itself as a direct, community-backed successor. With a clear commitment to long-term support and a governance model under the AlmaLinux OS Foundation, AlmaLinux emerges as a compelling choice for users seeking continuity and stability. While CentOS has a strong legacy, AlmaLinux’s focused direction and community-driven approach position it as a promising alternative for those prioritizing uninterrupted support and compatibility with RHEL.