I’ve been directly involved with the deployment of Red Hat OpenShift Platform on bare metal using the Red Hat OpenStack Platform director deployment/management tool, integrated with openshift-ansible. I’ll give some details of this demo, the upstream TripleO features related to this work, and insight around the potential use-cases.
TripleO & Ansible, a Powerful Combination!
For anyone that’s used Red Hat OpenStack Platform director (or the upstream TripleO project, upon which it is based), you’re familiar with the model of deploying a management node (“undercloud” in TripleO terminology), then deploying and managing your OpenStack nodes on bare metal. However, TripleO also provides a very flexible and powerful combination of planning, deployment, and day-2 operations features. For instance, director allows us to manage and provision bare metal nodes, then deploy virtually any application onto those nodes via Ansible!
The “undercloud” management node makes use of several existing OpenStack services, including Ironic for discovery/introspection and provisioning of bare metal nodes, Heat, a declarative orchestration tool, and Mistral, a workflow engine. It also provides a convenient UI, showcased in the demo, along with flexible CLI interfaces and standard OpenStack ReST APIs for automation.
As described in the demo, director has many useful features for managing your hardware inventory - you can either register or auto-discover your nodes, then do introspection (with optional benchmarking tests) to discover the hardware characteristics via the OpenStack ironic-inspector service. Nodes can then be matched to a particular profile either manually or via rules implemented through the OpenStack Mistral workflow API. You are then ready to deploy an Operating System image onto the nodes using the OpenStack Ironic “bare metal-as-a-service” API.
When deciding what will be deployed onto your nodes, director has the concept of a “deployment plan,” which combines specifying which nodes/profiles will be used and which configuration will be applied, known as “roles” in TripleO terminology.
This is a pretty flexible system enabling a high degree of operator customization and extension through custom roles where needed, as well as supporting network isolation and custom networks (isolated networks for different types of traffic), declarative configuration of network interfaces, and much more!
Deploying Red Hat OpenShift Container Platform on bare metal
What was new in the Summit demo was deploying OpenShift alongside OpenStack, both on bare metal, and both managed by Red Hat OpenStack Platform director. Over the last few releases we’ve made good progress on ansible integration in TripleO, including enabling integration with “external” installers. We’ve made use of that capability here to deploy OpenShift via TripleO, combining the powerful bare-metal management capabilities of TripleO with existing openshift-ansible management of configuration.
Integration between Red Hat OpenStack Platform and Red Hat OpenShift Container Platform
Something we didn’t have time to get into in great detail during the demo was the potential for integration between OpenStack and OpenShift - if you have an existing Red Hat OpenStack Platform deployment you can choose to deploy OpenShift with persistent volumes backed by Cinder (the OpenStack block storage service). And for networking integration, the Kuryr project, combined with OVN from OpenvSwitch, enables the sharing of a common overlay network between both platforms, without the overhead of double encapsulation.
This makes it easy to add OpenShift managed containers to your infrastructure, while almost seamlessly integrating them with VM workloads running on OpenStack. You can also take advantage of existing OpenStack capacity and vendor support while using the container management capabilities of OpenShift.
After we deployed OpenShift we saw some exciting demos focussed on workloads running on OpenShift, including a preview of the new container native virtualization (CNV) feature. CNV uses the upstream KubeVirt project to run Virtual Machine (VM) workloads directly on OpenShift.
Unlike the OpenShift and OpenStack combination described above, here OpenShift manages the VM workloads, providing an easier way to transition your VM workloads where no existing virtualization solution is in place. The bare-metal deployment capabilities outlined earlier are particularly relevant here, as you may want to run OpenShift worker nodes that host VMs on bare metal for improved performance. As the demo has shown, the combination of director and openshift-ansible makes deploying, managing, and running OpenShift and OpenStack easier to achieve!