AWS Hosted Control Plane Deployment#

Follow these steps to set up a k0smotron-hosted control plane on AWS:

Prerequisites

Before proceeding, make sure you have the following:
- A management Kubernetes cluster (Kubernetes v1.28 or later) deployed on AWS with k0rdent installed.
- A default storage class configured on the management cluster to support Persistent Volumes.
- The VPC ID where the worker nodes will be deployed.
- The Subnet ID and Availability Zone (AZ) for the worker nodes.
- The AMI ID for the worker nodes (Amazon Machine Image ID for the desired OS and Kubernetes version).
Important

All control plane components for your hosted cluster will reside in the management cluster, and the management cluster must have sufficient resources to handle these additional workloads.
Networking

To deploy a hosted control plane, the necessary AWS networking resources must already exist or be created. If you're using the same VPC and subnets as your management cluster, you can reuse these resources.

If your management cluster was deployed using the Cluster API Provider AWS (CAPA), you can gather the required networking details using the following commands:

Retrieve the VPC ID:
```
kubectl get awscluster <cluster-name> -o go-template='{{.spec.network.vpc.id}}'
```
Retrieve Subnet ID:
```
kubectl get awscluster <cluster-name> -o go-template='{{(index .spec.network.subnets 0).resourceID}}'
```
Retrieve Availability Zone:
```
kubectl get awscluster <cluster-name> -o go-template='{{(index .spec.network.subnets 0).availabilityZone}}'
```
Retrieve Security Group:
```
kubectl get awscluster <cluster-name> -o go-template='{{.status.networkStatus.securityGroups.node.id}}'
```
Retrieve AMI ID:
```
kubectl get awsmachinetemplate <cluster-name>-worker-mt -o go-template='{{.spec.template.spec.ami.id}}'
```
Tip

If you want to use different VPCs or regions for your management and hosted clusters, you’ll need to configure additional networking, such as VPC peering, to allow communication between them.

Create the ClusterDeployment manifest

Once you've collected all the necessary data, you can create the ClusterDeployment manifest. This file tells k0rdent how to deploy and manage the hosted control plane. For example:

apiVersion: k0rdent.mirantis.com/v1alpha1
kind: ClusterDeployment
metadata:
  name: aws-hosted-cp
spec:
  template: aws-hosted-cp-0-1-0
  credential: aws-credential
  config:
    clusterLabels: {}
    vpcID: vpc-0a000000000000000
    region: us-west-1
    publicIP: true
    subnets:
      - id: subnet-0aaaaaaaaaaaaaaaa
        availabilityZone: us-west-1b
        isPublic: true
        natGatewayID: xxxxxx
        routeTableId: xxxxxx
      - id: subnet-1aaaaaaaaaaaaaaaa
        availabilityZone: us-west-1b
        isPublic: false
        routeTableId: xxxxxx
    instanceType: t3.medium
    securityGroupIDs:
      - sg-0e000000000000000

Note

The example above uses the us-west-1 region, but you should use the region of your VPC.

Generate the ClusterDeployment Manifest

To simplify the creation of a ClusterDeployment manifest, you can use the following template, which dynamically inserts the appropriate values:

apiVersion: k0rdent.mirantis.com/v1alpha1
kind: ClusterDeployment
metadata:
  name: aws-hosted
spec:
  template: aws-hosted-cp-0-1-0
  credential: aws-credential
  config:
    clusterLabels: {}
    vpcID: "{{.spec.network.vpc.id}}"
    region: "{{.spec.region}}"
    subnets:
    {{- range $subnet := .spec.network.subnets }}
      - id: "{{ $subnet.resourceID }}"
        availabilityZone: "{{ $subnet.availabilityZone }}"
        isPublic: {{ $subnet.isPublic }}
        {{- if $subnet.isPublic }}
        natGatewayId: "{{ $subnet.natGatewayId }}"
        {{- end }}
        routeTableId: "{{ $subnet.routeTableId }}"
    {{- end }}
    instanceType: t3.medium
    securityGroupIDs:
      - "{{.status.networkStatus.securityGroups.node.id}}"

Save this template as clusterdeployment.yaml.tpl, then generate your manifest using the following command:

kubectl get awscluster <cluster-name> -o go-template="$(cat clusterdeployment.yaml.tpl)" > clusterdeployment.yaml

Apply the ClusterTemplate

Nothing actually happens until you apply the ClusterDeployment manifest to create a new cluster deployment:
```
kubectl apply -f clusterdeployment.yaml -n kcm-system
```

Deployment Tips#

Here are some additional tips to help with deployment:

Controller and Template Availability:

Make sure the KCM controller image and templates are available in a public or accessible repository.

Install Charts and Templates:

If you're using a custom repository, run the following commands with the appropriate kubeconfig:

KUBECONFIG=kubeconfig IMG="ghcr.io/k0rdent/kcm/controller-ci:v0.0.1-179-ga5bdf29" REGISTRY_REPO="oci://ghcr.io/k0rdent/kcm/charts-ci" make dev-apply
KUBECONFIG=kubeconfig make dev-templates

Mark the Infrastructure as Ready:

To scale up the MachineDeployment, manually mark the infrastructure as ready:
```
kubectl patch AWSCluster <hosted-cluster-name> --type=merge --subresource status --patch '{"status": {"ready": true}}' -n kcm-system
```
For more details on why this is necessary, click here.