Project Atomic is now sunset

The Atomic Host platform is now replaced by CoreOS. Users of Atomic Host are encouraged to join the CoreOS community on the Fedora CoreOS communication channels.

The documentation contained below and throughout this site has been retained for historical purposes, but can no longer be guaranteed to be accurate.

Learning More

Read the Introduction to Project Atomic for information about the goals and scope of the project.

Getting Started

The Quick Start Guide. will help you get Atomic up and running quickly.

For more information about Project Atomic's desktop version, check out our temporary documentation about Fedora Atomic Workstation.

More In-depth Documentation

Updating the Atomic Host

Atomic hosts are updated using a tool called rpm-ostree. An easy way to think about rpm-ostree and its parent project OSTree is "git for operating systems."

Using rpm-ostree we can easily update the system in one "atomic" transaction, and roll back to the prior system if an update has any issues.

Managing Storage

To set up additional storage for /var/lib/docker see Setting Up Storage and when considering alternative filesystems see Supported Filesystems.

Atomic: /usr/bin/atomic

The Atomic (/usr/bin/atomic) Documentation explains how to use the atomic command on Atomic hosts. This command defines the entrypoint for Project Atomic hosts.

The goal of /usr/bin/atomic is to provide a high-level, coherent entrypoint to the system, and fill in gaps that are not filled by Linux container implementations.

Containment and Security

Beyond the isolation provided by containers, Atomic relies on Security-Enhanced Linux to improve the security of the host and between containers, see Docker and SELinux for details of the increased protection available.


When an application is composed using multiple containers it can be a bit complex to provide for communication without losing flexibility. Learn about Atomic host networking options for single and multi-host configurations.

How to Contribute to the Documentation

Atomic is a work in progress, and documentation needs to follow the pace of the developments.

To help achieve this, the documentation (as well as the whole web site) is available from the atomic-site repository on GitHub as part of the projectatomic framework. Most of the documents are simply written in the Markdown plain text formatting syntax, they are as a result easy to edit and extend. To change a document, clone the atomic site and make your edits under the sources/docs/ directory. If you add a new file please also register it in data/docs.yml . Then send us a pull request on GitHub or the resulting patch to the atomic-devel mailing-list if you prefer. Thanks !

The web site itself is available in the atomic-site repository on GitHub, it is built using Middleman framework, see the at the top of the git checkout for informations. It also uses Haml for more complex formatting of some pages, check the Tutorial to get started editing some of the haml pages.