CoreOS was founded in 2013 with the mission to improve the security and reliability of the internet. The team built cloud native open source software and products to enable companies to run their applications securely and reliably in any environment.
CoreOS developed open source tools that were the fundamental building blocks of modern distributed systems. The open source components continued to be freely used and developed to power cloud native distributed systems. Projects like etcd (distributed key-value store), Container Linux (lightweight container-centric OS), Kubernetes (container orchestrator), Prometheus (container monitoring system), and more continued to be developed by the CoreOS team as a part of Red Hat, the largest open source software company in the world.
Container Linux provided several key pieces of the modern, container-native operating system, most notably a fully immutable, container-optimized Linux host that includes automated, "over-the-air" updates, to keep large deployments up to date more easily.
As we've previously announced, Fedora CoreOS is the official successor to CoreOS Container Linux. Fedora CoreOS is a new Fedora Edition built specifically for running containerized workloads securely and at scale. It combines the provisioning tools and automatic update model of Container Linux with the packaging technology, OCI support, and SELinux security of Atomic Host. For more on the Fedora CoreOS philosophy, goals, and design, see the announcement of the preview release and the Fedora CoreOS documentation.
We'd love for you to try Fedora CoreOS and get involved. You can report bugs and missing features to the issue tracker and discuss Fedora CoreOS in Fedora Discourse, the development mailing list, in #fedora-coreos on Freenode, or at our weekly IRC meetings.
For more information about migrating to Fedora CoreOS, see the migration notes. Be aware that Fedora CoreOS cannot currently replace Container Linux for all use cases:
It does not yet include native support for Azure, DigitalOcean, GCE, Vagrant, or the Container Linux community-supported platforms.
The rkt container runtime is not included.
Fedora CoreOS provides best-effort stability, and may occasionally include regressions or breaking changes for some use cases or workloads.
We recommend making your own decisions about where and how to run Fedora CoreOS based on your use case, operational needs, and experience.
Effective immediately, the CoreOS Container Linux listing on AWS Marketplace will no longer be available to new subscribers. Note that this does not affect existing subscribers to Container Linux on AWS Marketplace, nor does it affect users launching Container Linux via the AMI IDs that were listed on the CoreOS download page.
On May 26, 2020 the final updates to CoreOS Container Linux were rolled out. Any bugs or security vulnerabilities discovered after that date will not be fixed.
On or after September 1, 2020, published resources related to CoreOS Container Linux will be deleted or made read-only. OS downloads will be removed, CoreUpdate servers will be shut down, and OS images will be removed from AWS, Azure, and Google Compute Engine. GitHub repositories, including the issue tracker, will become read-only. Documentation will continue to exist for as long as is practical, to aid migration to other operating systems. Existing Container Linux machines will continue running, but will no longer be able to download updates. New CoreOS Container Linux machines will not be launchable in public clouds without prior preparation.
We will be taking the unusual step of deleting CoreOS Container Linux artifacts and images after September 1, 2020 to discourage continued use after the OS is no longer receiving security updates.