What is CentOS?

CentOS is an open source project that releases 2 distinct Linux® distributions, CentOS Stream and CentOS Linux. It is also the open source community of people who participate in it and everything enabling them to work on CentOS project outputs. Red Hat®, Almalinux, CloudLinux, and AWS all contribute to this community.

CentOS Stream is the upstream development platform for upcoming Red Hat® Enterprise Linux product releases.

The CentOS Project will discontinue updates and releases of CentOS Linux® between 2021 and 2024. This means current CentOS Linux users will need to choose a migration path. Updates for CentOS Linux 8 ended in December 2021, and updates for CentOS Linux 7 will end on June 30, 2024. To aid in this transition, consider using the CentOS Linux migration assessment to find potential considerations for your specific needs and environment.

CentOS Linux and CentOS Stream are both are open source Linux distros, versions of CentOS, and part of the overall enterprise Linux ecosystem. CentOS Stream serves as the open source development platform for upcoming releases of Red Hat Enterprise Linux. CentOS Stream is what will become Red Hat Enterprise Linux, while CentOS Linux is derived from source code released by Red Hat. Historically, each version of CentOS Linux reflected major versions of Red Hat Enterprise Linux—both used the RPM package manager system and maintained similar functionality, compatibility, and bug fixes.

CentOS Stream serves as the open source development platform for upcoming minor releases of Red Hat Enterprise Linux. CentOS Stream makes Red Hat Enterprise Linux developmental source code available so community members–along with Red Hat partners and ecosystem developers–have a place to contribute and test code in tandem with Red Hat Enterprise Linux engineers. 

CentOS Linux is a community-supported distribution derived from source code released by Red Hat. It is built on the Linux kernel, which is most often used for software development and deployment and doesn’t have a distribution model. Updates to CentOS Linux will discontinue between 2021 and 2024. Historically, each version of CentOS Linux reflected major versions of Red Hat Enterprise Linux. Both used the RPM package manager system and maintained similar functionality, compatibility, and bug fixes. 

CentOS is an open source project. Red Hat Enterprise Linux is an enterprise open source product.

CentOS Stream, CentOS Linux, and Red Hat Enterprise Linux are all different Linux distributions (along with Ubuntu, Debian, Oracle Linux, Fedora Linux and others), and there are many technical, support, and developmental differences between them. Choosing the best Linux distribution for you depends on your use case and tool requirements.

• There are thousands of technical differences, like variances in binary execution paths. 
• The support structures are different. CentOS Stream and CentOS Linux support is provided by the goodwill of other users and contributors via GitHub, forums, wikis, tutorials, and other methods of collaboration. Red Hat Enterprise Linux is supported by full-time engineers and staff.
• The way they all invite, test, and commit source code modifications are different. Red Hat Enterprise Linux contributions are channeled through CentOS Stream. CentOS Stream contributions can be suggested by anyone, but contributions are only accepted and committed by Red Hat engineers. CentOS Linux doesn’t have a contribution model.

The CentOS Project will discontinue updates and releases of CentOS Linux between 2021 and 2024. This means current CentOS Linux users will need to choose a migration path. Updates for CentOS Linux 8 ended in December 2021, and updates for CentOS Linux 7 will end on June 30, 2024.

However, the CentOS community is not going away. Community contributors and CentOS users will continue to collaborate on open source Linux distributions as part of the CentOS Stream project, which will remain an important part of the Red Hat Enterprise Linux development process.

CentOS special interest groups (CentOS SIGs) will continue their activities within the community, based on the direction of each groups’ members and organizing leaders. Anyone can seek the CentOS governing board’s approval to start a new SIG.

CentOS Stream will continue to be the open source development platform and main development pipeline of Red Hat Enterprise Linux minor releases. 

• CentOS Stream 8 is part of the Red Hat Enterprise Linux 8 development process and updates will continue through the full support phase of the Red Hat Enterprise Linux 8 lifecycle.
• CentOS Stream 9 launched in 2021 as part of the Red Hat Enterprise Linux 9 development process with a similar update cycle.

CentOS Linux source code will remain available to the public on git.centos.org, but builds of  CentOS Linux 8 will end in December 2021. Organizations and communities providing CentOS Linux-like operating systems—such as Rocky Linux, Amazon Linux 2, Docker, and AlmaLinux—will need to be consulted directly since Red Hat and CentOS maintain no involvement in these efforts. Rocky Linux, which was founded by CentOS co-founder Gregory Kurtzer, will also continue creating CentOS Linux-like distributions. The CentOS governing board decided to sunset CentOS versions on the following schedule:

• CentOS Linux 7 updates will continue alongside Red Hat Enterprise Linux 7 support lifecycle through June 2024.
• CentOS Linux 8 updates ended December 31, 2021.
• CentOS Linux 9 will not launch.

Yes.

Qualifying individuals and organizations have access to several programs that provide Red Hat Enterprise Linux subscriptions at no cost (depending on certain variables). Red Hat tooling to support the migration is available and fully supported, as is the resulting deployment.

• Individual developers can sign up for a no-cost Red Hat Developer subscription.
• Red Hat Developer Subscription for Teams offers existing Red Hat customer organizations running Red Hat technologies in their production environments the opportunity to deploy Red Hat Enterprise Linux in their development environments at no extra cost.
• Open source projects, communities, and other nonprofit software groups engaged with open source may qualify for a no-cost Red Hat Open Source Infrastructure program. 
• Academic institutions and nonprofit research institutions may be able to access Red Hat Enterprise Linux at a reduced rate through the Red Hat Academic Program.

CentOS Stream includes the kernel and all user space components, and is where the primary RHEL + 1 development occurs. It enables a quicker route to market for independent software vendors (ISVs), independent hardware vendors (IHVs), original equipment manufacturers (OEMs), and Red Hat layered products.

There are 2 main ways to start using CentOS Stream.