I'm not sure of the all the details related to Atomic, but my understanding is that you're correct in its smaller marketshare. Unlike Container Linux, I personally don't know how much time we're going to continue to maintain the distribution. I know there is public information somewhere; I'm going to fire off an email to get more information so that I can clarify this post.

Going forward RHEL and Red Hat CoreOS are going to be the official distributions supported for running OpenShift. RHEL will be for users that need to install software on the hosts themselves manually and CoreOS will be the preferred immutable host that expects all software running at the cluster-level. Running OpenShift on Container Linux or Atomic will be like running RHEL RPMs on CentOS -- it'll pretty much work fine, but I don't think you can call up Red Hat if you get into trouble.

rpm-ostree is super cool. The engineers working on the OS are still trying to figure out how to bring everything together, but we understand how important this technology is. I know this is the hill where the Atomic engineers will die on, so if there's going to be anything from Atomic in CoreOS, it's going to be this, haha.

The answer to this splits across the Fedora/RHEL sides. For people using RHEL Atomic Host today (and RHEL) with OpenShift, we obviously want a good transition to Red Hat CoreOS. That gets into some details though of provisioning and what types of customization is being done today. Similar concerns apply to Tectonic+CL users.

My message on the community side (Fedora and existing CL) is - don't panic, you have some time. And a lot of us want to support a broad array of use cases.

Since you mention rpm-ostree, one thing I'd point you to is some work we did on changing the Container Linux update operator to talk to it: https://github.com/ashcrow/container-linux-update-operator/

So, it depends on which Atomic.

Fedora Atomic Host will be updated through at least the end of Fedora 28 cycle (december?). I'd like to keep it updated through Fedora 29, but we'll see what actually happens; best intentions aside, build engineers are always in short supply (your contributions can help). Red Hat Atomic Host will be supported into 2020. Centos Atomic Host tracks RHAH, so it will likely be available through the same period.

After that ... there will be some kind of migration plan to the new OS, details TBD. The real asset we have there is `rpm-ostree rebase` which makes it really easy to swap out the Atomic Host base in-place.

Also, I'd really like to know how you're deploying Kubernetes on Atomic, because we will likely stop building some of the multiple ways to install K8s on Atomic, and would prefer to keep the ones people are actually using.