TripleO

OpenStack Containerization with Podman – Part 1 (Undercloud)

In this series of blog posts, we’ll demonstrate how we can replace Docker by Podman when deploying OpenStack containers with TripleO.

Group of seals, also named as a pod
Group of seals, also named as a pod

This first post will focus on the Undercloud (the deployment cloud) which contains the necessary components to deploy and manage an “Overcloud” (a workload cloud). During the Rocky release, we switched the Undercloud to be containerized by default, using the same mechanism as we did for the Overcloud. If you need to be convinced by Podman, I strongly suggest to see this talk but in short, Podman bring more security and make systems more lightweight. It also brings containers into a Kubernetes friendly environment.

Note: Deploying OpenStack on top of Kubernetes isn’t in our short-term roadmap and won’t be discussed during these blog posts for now.

To reproduce this demo, you’ll need to follow the official documentation which explains how to deploy an Undercloud but change the undercloud.conf to have container_cli = podman (instead of default docker for now).

In the next post, we’ll talk about operational changes when containers are managed with Podman versus Docker.

Software Engineeer at Red Hat, Private Pilot, French guy hiding somewhere in Canada.