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.
A new Fedora Atomic Host update is available via an OSTree commit:
Commit: 3fd888c674c6d69907eabc665103341e01ebe3a04c3876af6cac673b0bf43662
Version: 25.122
Unfortunately we had some release engineering hiccups last week. Which caused us to not have a release candidate with all the fixes we needed until Friday. We will get back on track next week.
Notable updates are the atomic CLI, ostree and rpm-ostree.
One of the major benefits of the overlay2 filesystem for Docker is that you no longer need to have a separate storage volume for your Docker containers, images and volumes. This means that you don’t need to try to decide how much free space you need in the root FS as opposed to how much you need for containers; you can just create one big volume to fill up the disk.
Since overlay2 is fairly new, though, we’ve chosen to install a separate Docker volume by default on Fedora 26 Atomic Host. This lets users switch back to devicemapper if they run into some kind of issue with overlay2. However, if you’re installing a new dev system, you might want the ease-of-management of having one big volume.
I’ve blogged here in the past about different ways of running Kubernetes and its dependencies in containers. In that post, I discussed how you could side-step the chicken-and-egg complexities of trying to use Docker to run components on which Docker itself relies by running Flannel and etcd in system containers, which don’t rely on Docker to run.
Recently, I’ve been working on running Kubernetes in system containers, too. Since I was already running etcd and Flannel in system containers, I could save on a bit of storage by having Flannel, etcd, and Kubernetes all share the same image in the ostree-based storage that system containers use.
On the Project Atomic mailing list, Colin Walters posted
a quick set of instructions on how to migrate the Docker storage driver from devicemapper to overlay2 on Fedora Atomic Host.
The overlay2 driver will be the default storage driver in Fedora 26, but you can use it on Fedora 25 Atomic now. To switch storage drivers on an installed system, either before or after you rpm-ostree rebase to Fedora 26, you can use the following procedure.
We are happy to introduce you to Minishift, providing a better user experience than our original Atomic Developer Bundle (ADB). We have shifted our development effort from ADB to Minishift, both to improve user experience, and to address the issues caused by depending on Vagrant. We’ll explain this more in a later blog post.
Minishift is a CLI tool that helps you run OpenShift locally by running a single-node cluster inside a VM. You can try out OpenShift or develop with it, day-to-day, on your local host.