CentOS. The name evokes images of rock-solid servers humming away in data centers, powering websites, databases, and countless critical applications. For years, CentOS has been a cornerstone of the Linux ecosystem, offering a free, enterprise-grade operating system derived from the source code of Red Hat Enterprise Linux (RHEL). This blog post delves into the history, features, use cases, and recent changes surrounding CentOS, providing a comprehensive overview for both newcomers and seasoned Linux users.

A Legacy of Stability and Reliability:

CentOS's story is intertwined with that of RHEL. Red Hat, a leading provider of open-source solutions, develops RHEL as a commercially supported Linux distribution targeted at businesses. RHEL is known for its stability, long-term support, and rigorous testing. CentOS emerged as a community-driven project that rebuilt RHEL's source code, removing Red Hat's branding and trademarks, to offer a free-to-use equivalent. Explore the replacement for centos in our detailed guide.

This approach provided several key benefits: 

• Binary Compatibility: CentOS maintained binary compatibility with RHEL, meaning applications compiled for RHEL could run seamlessly on CentOS. This made it an attractive option for developers testing software for RHEL deployments.
• Long-Term Support: Like RHEL, CentOS offered extended support cycles, typically around 10 years. This long-term stability was crucial for production environments where frequent upgrades were undesirable.
• Free of Charge: The absence of licensing fees made CentOS a popular choice for individuals, small businesses, and organizations looking for a robust and reliable server operating system without the financial burden.

Key Features and Use Cases:

CentOS's strengths made it a go-to choice for various applications:

• Web Servers: CentOS's stability and performance made it ideal for hosting web servers using Apache, Nginx, and other web server software.
• Database Servers: Databases like MySQL, MariaDB, and PostgreSQL thrived on CentOS, benefiting from its robust architecture and long-term support.
• Enterprise Applications: Many enterprise-grade applications were certified to run on RHEL, and therefore also on CentOS, making it a suitable platform for business-critical software.
• Cloud Computing: CentOS was a popular choice for cloud deployments, providing a stable and predictable environment for virtual machines and containers.
• Development and Testing: Developers often used CentOS as a development and testing platform, ensuring compatibility with RHEL deployments in production.

The Shift to CentOS Stream:

In late 2020, Red Hat announced a significant change to the CentOS project. The traditional CentOS Linux distribution, which was a rebuild of RHEL after its release, was discontinued. In its place, Red Hat introduced CentOS Stream, a rolling-release distribution that serves as an upstream development platform for RHEL.

This change caused considerable debate and concern within the Linux community. The key differences between CentOS Linux and CentOS Stream are:

• CentOS Linux: Downstream rebuild of RHEL (released after RHEL). Focus on stability and long-term support.
• CentOS Stream: Upstream development platform for RHEL (released before RHEL). Focus on innovation and faster updates.

Impact and Alternatives:

The shift to CentOS Stream had a profound impact on the Linux landscape. Users who relied on the stable, downstream nature of CentOS Linux were left searching for alternatives. Several distributions emerged as potential replacements:

• Rocky Linux: Founded by Gregory Kurtzer, the original founder of the CentOS project, Rocky Linux aims to be a true downstream rebuild of RHEL, providing a stable and long-term supported alternative.
• AlmaLinux: Another community-driven project, AlmaLinux also focuses on providing a free, binary-compatible replacement for CentOS Linux.
• Oracle Linux: While not a community-driven project, Oracle Linux offers a free distribution based on RHEL, with optional commercial support from Oracle.

The Role of CentOS Stream:

While not a direct replacement for the old CentOS Linux, CentOS Stream plays an important role in the RHEL development process. It allows developers and the community to test and contribute to future versions of RHEL, providing a more collaborative and transparent development model.

Conclusion:

CentOS, in its various forms, has played a pivotal role in the Linux ecosystem. The traditional CentOS Linux provided a stable and reliable platform for countless applications, while CentOS Stream now serves as a crucial part of the RHEL development pipeline. The discontinuation of CentOS Linux has led to the emergence of strong alternatives like Rocky Linux and AlmaLinux, ensuring that the need for free, enterprise-grade Linux distributions continues to be met. While the landscape has shifted, the core principles of stability, reliability, and open-source collaboration remain at the heart of the Linux community. Whether you choose a downstream rebuild like Rocky Linux or AlmaLinux, or engage with the upstream development of CentOS Stream, the legacy of CentOS continues to shape the future of enterprise Linux.