Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Starting with MOSK 25.2, the MOSK documentation set will cover all product layers, including MOSK management (formerly MCC). This means everything you need will be in one place. The separate MCC documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

OpenStack Controller (Rockoon)

The OpenStack Controller (Rockoon) runs in a set of containers in a pod in Kubernetes. Rockoon is deployed as a Deployment with 1 replica only. The failover is provided by Kubernetes that automatically restarts the failed containers in a pod.

However, given the recommendation to use a separate Kubernetes cluster for each OpenStack deployment, the controller in envisioned mode for operation and deployment will only manage a single OpenStackDeployment resource, making the proper HA much less of an issue.

Rockoon is written in Python using Kopf, as a Python framework to build Kubernetes operators, and Pykube, as a Kubernetes API client.

Using Kubernetes API, the controller subscribes to changes to resources of kind: OpenStackDeployment, and then reacts to these changes by creating, updating, or deleting appropriate resources in Kubernetes.

The basic child resources managed by the controller are Helm releases. They are rendered from templates taking into account an appropriate values set from the main and features fields in the OpenStackDeployment resource.

Then, the common fields are merged to resulting data structures. Lastly, the services fields are merged providing the final and precise override for any value in any Helm release to be deployed or upgraded.

The constructed values are then used by Rockoon during a Helm release installation.

Rockoon containers

Container	Description
osdpl	The core container that handles changes in the osdpl object.
helmbundle	The container that watches the helmbundle objects and reports their statuses to the osdpl object in status:children. See OpenStackDeploymentStatus custom resource for details.
health	The container that watches all Kubernetes native resources, such as Deployments, Daemonsets, Statefulsets, and reports their statuses to the osdpl object in status:health. See OpenStackDeploymentStatus custom resource for details.
secrets	The container that provides data exchange between different components such as Ceph.
node	The container that handles the node events.