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.

Project News

Docker, CentOS 6, and You

by Jason Brooks –

Recently, I blogged about docker-on-loopback-storage woes and workarounds – a topic that came up during several conversations I had at last month’s Dockercon. Another frequently-discussed item from the conference involved Docker on CentOS 6, and whether and for how long users can count on running this combination.

Docker and CentOS 6 have never been a terrific fit, which shouldn’t be surprising considering that the version of the Linux kernel that CentOS ships was first released over three years before Docker’s first public release (0.1.0). The OS and kernel version you use matter a great deal, because with Docker, that’s where all your contained processes run.

With a hypervisor such as KVM, it’s not uncommon or problematic for an elder OS to host, through the magic of virtualization, all manner of bleeding-edge software components. In fact, if you’re attached to CentOS 6, virtualization is a solid option for running containers in a more modern, if virtual, host.

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Project Atomic at ContainerCon

by Joe Brockmeier –

Attending ContainerCon in Seattle this year? Co-located with CloudOpen and LinuxCon, ContainerCon is focused on bringing contributors working with containers, the Linux kernel, and other components together to continue improving the Linux container ecosystem.

As you might expect, there’s quite a few talks on the schedule related to Project Atomic or components important to Atomic (like Kubernetes). Here’s a sample of talks you might want to plan on seeing:

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Creating a Simple Bare Metal Atomic Host Cluster

by Waldemar Augustyn –

Atomic host is a great technology for containerized applications. I like it especially on bare metal machines. In this post I will describe how to setup a simple Do-It-Yourself cluster consisting of three netbooted machines running docker over flannel. Flannel provides a NAT-less private network overlay. Through that network, application containers can easily reach any other containers within the cluster regardless of which machine they run on.

We use three machines called a1, a2, and a3. Let’s designate static IP addresses to them.

  • a1: 192.168.99.51
  • a2: 192.168.99.52
  • a3: 192.168.99.53

We install atomic host OS on these machines via netboot from another host. Let’s call that host boothost. It holds all installation and configuration files. We set up an unattended installation and configuration using kickstart and cloud-init.

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Friends Don't Let Friends Run Docker on Loopback in Production

by Jason Brooks –

I’ve heard negative things about the Fedora|CentOS Docker storage configuration in the past, and while manning the Red Hat booth in San Francisco at DockerCon last week, I spoke to a number of people who’ve experienced these storage issues themselves.

Much of the trouble, I think, boils down to how Docker in Fedora and CentOS have shipped with a storage configuration that optimizes for a convenient getting started experience that can lead to inconvenience down the road.

I’ll cover how to reconfigure your Docker installation w/ better-performing storage, but first, a bit of background:

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