Overview

Mirantis Container Cloud is a set of microservices that are deployed using Helm charts and run in a Kubernetes cluster. Container Cloud is based on the Kubernetes Cluster API community initiative.

The following diagram illustrates an overview of Container Cloud and the clusters it manages:

../_images/cluster-overview.png

All artifacts used by Kubernetes and workloads are stored on the Container Cloud content delivery network (CDN):

  • mirror.mirantis.com (Debian packages including the Ubuntu mirrors)

  • binary.mirantis.com (Helm charts and binary artifacts)

  • mirantis.azurecr.io (Docker image registry)

All Container Cloud components are deployed in the Kubernetes clusters. All Container Cloud APIs are implemented using the Kubernetes Custom Resource Definition (CRD) that represents custom objects stored in Kubernetes and allows you to expand Kubernetes API.

The Container Cloud logic is implemented using controllers. A controller handles the changes in custom resources defined in the controller CRD. A custom resource consists of a spec that describes the desired state of a resource provided by a user. During every change, a controller reconciles the external state of a custom resource with the user parameters and stores this external state in the status subresource of its custom resource.

Container Cloud cluster types

The types of the Container Cloud clusters include:

Bootstrap cluster

  • Runs the bootstrap process on a seed data center bare metal node that can be reused after the management cluster deployment for other purposes.

  • Requires access to the bare metal provider backend.

  • Initially, the bootstrap cluster is created with the following minimal set of components: Bootstrap Controller, public API charts, and the Bootstrap API.

  • The user can interact with the bootstrap cluster through the Bootstrap API to create the configuration for a management cluster and start its deployment. More specifically, the user performs the following operations:

    1. Create required deployment objects.

    2. Optionally add proxy and SSH keys.

    3. Configure the cluster and machines.

    4. Deploy a management cluster.

  • The user can monitor the deployment progress of the cluster and machines.

  • After a successful deployment, the user can download the kubeconfig artifact of the provisioned cluster.

Management cluster

Comprises Container Cloud as product and provides the following functionality:

  • Runs all public APIs and services including the web UIs of Container Cloud.

  • Does not require access to any provider backend.

  • Runs the provider-specific services and internal API including LCMMachine and LCMCluster. Also, it runs an LCM controller for orchestrating managed clusters and other controllers for handling different resources.

  • Requires two-way access to a provider backend. The provider connects to a backend to spawn managed cluster nodes, and the agent running on the nodes accesses the regional cluster to obtain the deployment information.

For deployment details of a management cluster, see Deployment Guide.

Managed cluster

  • A Mirantis Kubernetes Engine (MKE) cluster that an end user creates using the Container Cloud web UI.

  • Requires access to its management cluster. Each node of a managed cluster runs an LCM Agent that connects to the LCM machine of the management cluster to obtain the deployment details.

  • Supports Mirantis OpenStack for Kubernetes (MOSK). For details, see MOSK documentation.

All types of the Container Cloud clusters except the bootstrap cluster are based on the MKE and Mirantis Container Runtime (MCR) architecture. For details, see MKE and MCR documentation.

The following diagram illustrates the distribution of services between each type of the Container Cloud clusters:

../_images/cluster-types.png