This week, the Fedora Project released updated images for its Fedora 24-based Atomic Host. Fedora Atomic Host is a leading-edge operating system designed around Kubernetes and Docker containers.

Fedora Atomic Host images are updated roughly every two weeks, rather than on the main six-month Fedora cadence. Because development is moving quickly, only the latest major Fedora release is supported.

Note: Due to an issue with the image-building process, the current Fedora Atomic Host images include an older version of the system tree. Be sure to atomic host upgrade to get the latest set of components. The next two-week media refresh will include an up-to-date tree.

Fedora Atomic Host includes these core component versions:

  • kernel-4.6.4-301.fc24.x86_64
  • docker-1.10.3-24.git29066b4.fc24.x86_64
  • kubernetes-1.2.0-0.24.git4a3f9c5.fc24.x86_64
  • atomic-1.10.5-1.gitce09e40.fc24.x86_64
  • rpm-ostree-2016.4-2.fc24.x86_64
  • flannel-0.5.5-6.fc24.x86_64
  • etcd-2.2.5-5.fc24.x86_64
  • cloud-init-0.7.6-8.20150813bzr1137.fc24.noarch

Upgrading

Upgrading from an existing Atomic Host to Fedora Atomic 24 involves replacing the Fedora 23-based fedora-atomic remote with the current one, and then rebasing on the new tree. Due to this issue, it may be necessary to put SELinux into permissive mode for the rebase operation:

$ sudo setenforce 0
$ sudo ostree remote delete fedora-atomic
$ sudo ostree remote add fedora-atomic --set=gpg-verify=false https://dl.fedoraproject.org/pub/fedora/linux/atomic/24
$ sudo rpm-ostree rebase fedora-atomic:fedora-atomic/24/x86_64/docker-host
$ sudo reboot

Atomic Images

Fedora Atomic Host is available as a virtualbox or libvirt vagrant image, as an installable iso image, as a raw or qcow2-formatted cloud image, or as an Amazon AMI.

To bring up Fedora Atomic Host in a vagrant box, issue a command like:

vagrant init fedora/24-atomic-host && vagrant up

If you’ve previously used vagrant to run a Fedora Atomic 24 VM, first run vagrant box update --box=fedora/24-atomic-host to ensure that you have the latest version.

Note: Due to this issue, you’ll need to add a line to your Vagrantfile like config.vm.synced_folder "./", "/vagrant", disabled: 'true' to disable folder sync.

Fedora Atomic Host is available as a qcow2 or raw-formatted image, both of which require a cloud-init data source, be it from your cloud or virtualization provider, or from a local source.

The Fedora Project maintains Atomic Host images for Amazon EC2 in both GP2 (SSD-based) and standard formats. Check out the atomic host download page for AMI IDs specific to your desired region.

There’s also an anaconda-based ISO installer for use with bare metal or as an alternative to configuring cloud-init for virtual machines.

Get Involved

To get involved with Fedora Atomic Host, get in touch with the Fedora Cloud SIG. The SIG meets each week on Wednesdays at 17:00 UTC in the #fedora-meetings-1 channel, and hangs out in the #fedora-cloud channel and on the Fedora Cloud mailing list.

One of the best ways help out with Fedora Atomic is to participate in testing core atomic host components using Fedora’s Bodhi. Following this link will provide a list of key atomic packages currently in need of testing for Fedora 24.

The Fedora Project maintains a version of the Fedora Atomic system tree that includes packages from the updates-testing repo. Rebasing an atomic host to this tree is a handy way to run the latest packages in need of testing:

$ sudo rpm-ostree rebase fedora-atomic:fedora-atomic/24/x86_64/testing/docker-host
$ sudo systemctl reboot

If you have questions about how best to test one of these packages, ask on the Fedora Cloud mailing list or in the #fedora-cloud in irc.