CLI

For purposes of automation, it is strongly recommended that users create "version controlled" declaraive cluster specification files to provision and manage the lifecycle of Kubernetes clusters.

Important

Users need to use only a single command (rctl apply -f cluster_spec.yaml) for both provisioning and ongoing lifecycle operations. The controller will automatically determine the required changes and seamlessly map them to the associated action (e.g. add nodes, remove nodes, upgrade Kubernetes, update blueprint etc).

Create Cluster¶

Declarative¶

You can create an Upstream k8s cluster based on a version controlled cluster spec that you can manage in a Git repository. This enables users to develop automation for reproducible infrastructure.

./rctl apply -f <cluster file name.yaml>

An illustrative example of the split cluster spec YAML file for MKS is shown below

apiVersion: infra.k8smgmt.io/v3
kind: Cluster
metadata:
  name: test-mks
  project: defaultproject
  labels:
    check1: value1
    check2: value2
spec:
  blueprint:
    name: default
    version: latest
  config:
    autoApproveNodes: true
    dedicatedMastersEnabled: false
    highAvailability: false
    kubernetesVersion: v1.25.2
    location: sanjose-us
    network:
      cni:
        name: Calico
        version: 3.19.1
      podSubnet: 10.244.0.0/16
      serviceSubnet: 10.96.0.0/12
    nodes:
    - arch: amd64
      hostname: ip-172-31-61-40
      operatingSystem: Ubuntu20.04
      privateip: 172.31.61.40
      roles:
      - Master
      - Worker
      - Storage
      ssh:
        ipAddress: 35.86.208.181
        port: "22"
        privateKeyPath: mks-test.pem
        username: ubuntu
  type: mks

Important

Illustrative examples of "cluster specifications" are available for use in this Public Git Repository.

Once the rctl create command is executed successfully, following actions will be done:

Create cluster on the controller
Download conjurer & credentials
SCP conjurer & credentials to node
Run conjurer
Configure role, interface
Start provision

Note

At this time only SSH key based authentication is supportted to scp into the nodes

Provision Status¶

During cluster provisioing, status can be monitored as shown below.

./rctl get cluster <cluster-name> -o json | jq .status

The above command will return READY when the provision is complete.

Add Nodes¶

Users can add nodes on the cluster and update the config yaml file with the below command

./rctl apply -f <cluster-filename.yaml>

Example:

Add the below node details in the yaml file under the nodes key

- hostname: rctl-mks-1
  operatingSystem: "Ubuntu18.04"
  arch: amd64
  privateIP: 10.109.23.6
  roles:
    - Worker
    - Storage
  labels:
      key1: value1
      key2: value2
  taints:
    - effect: NoSchedule
      key: app
      value: infra
  ssh:
    privateKeyPath: "ssh-key-2020-11-11.key"
    ipAddress: 10.109.23.6
    userName: ubuntu
    port: 22

Use the below command to update the yaml file and add the nodes to the cluster

./rctl apply -f <cluster_filename.yaml>

Once the rctl update command is executed succesfully, following actions will be done:

Download conjurer & credentials
SCP conjurer & credentials to node
Run conjurer
Configure role, interface
Start provision

For more examples of MKS cluster spec, refer here

Node Provision Status¶

Once the node is added, Provision will trigger and provision status can be monitored as shown below.

rctl get cluster <cluster-name> -o json |  jq -r -c '.nodes[] | select(.hostname=="<hostname of the node>") | .status'

The above command will return READY when the provision is complete.

K8s Upgrade Strategy¶

To upgrade the nodes, incorporate the strategy parameters into the specification, whether opting for a concurrent or sequential approach. Here is an illustrative configuration file where the corresponding parameters have been integrated.

Important

Ability to specify upgrade strategy within the spec is currently only available in the [Preview](../../releasenotes/2023/sept.md/#v20-preview-saas) environment.

apiVersion: infra.k8smgmt.io/v3
kind: Cluster
metadata:
  name: qc-mks-cluster-1
  project: test-project
spec:
  blueprint:
    name: default
  config:
    autoApproveNodes: true
    kubernetesVersion: v1.26.5
    kubernetesUpgrade:
      strategy: concurrent
      params:
        workerConcurrency: "80%"
    network:
      cni:
        name: Calico
        version: 3.24.5
      ipv6:
        podSubnet: 2001:db8:42:0::/56
        serviceSubnet: 2001:db8:42:1::/112
      podSubnet: 10.244.0.0/16
      serviceSubnet: 10.96.0.0/12
    nodes:
    - arch: amd64
      hostname: mks-node-1
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.81
      roles:
      - Worker
      - Master
      ssh: {}
    - arch: amd64
      hostname: mks-node-2
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.155
      roles:
      - Worker
      ssh: {}
    - arch: amd64
      hostname: mks-node-3
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.169
      roles:
      - Worker
      ssh: {}
    - arch: amd64
      hostname: mks-node-4
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.196
      roles:
      - Worker
      ssh: {}
    - arch: amd64
      hostname: mks-node-5
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.115
      roles:
      - Worker
      ssh: {}
    - arch: amd64
      hostname: mks-node-6
      operatingSystem: Ubuntu20.04
      privateip: 10.0.0.159
      roles:
      - Worker
      ssh: {}
    proxy: {}
  type: mks

For the Concurrent strategy, assign a value to workerConcurrency, whereas in the case of the Sequential strategy, workerConcurrency is not required. Refer K8s Upgrade page for more information.

Delete Cluster¶

Users can delete one or more clusters with a single command

./rctl delete cluster <mkscluster-name>

(or)

./rctl delete cluster <mkscluster1-name> <mkscluster2-name>

Dry Run¶

The dry run command is utilized for operations such as Cluster Provisioning, K8s upgrades, blueprint upgrades, and node operations(e.g. :Node Addition/Node Deletion/Labels/Taints). It provides a pre-execution preview of changes, enabling users to assess potential modifications before implementation. This proactive approach is beneficial for identifying and addressing issues, ensuring that the intended changes align seamlessly with infrastructure requirements. Whether provisioning a new cluster or managing updates, incorporating a dry run enhances the predictability, reliability, and overall stability of your infrastructure.

./rctl apply -f <cluster_filename.yaml> --dry-run

Example

Node Addition - Day 2 operation

Below is an example of the output from the dry run command when a user tries to add a node on Day 2:

./rctl apply -f cluster_file.yaml --dry-run
Running echo $HOSTNAME on 34.211.224.152
Running PATH=$PATH:/usr/sbin ip -f inet addr show on 34.211.224.152
Running command -v bzip2 on 34.211.224.152 to verify if bzip2 is present on node
Running command -v wget on 34.211.224.152 to verify if wget is present on node
{
  "operations": [
    {
      "operation": "NodeAddition",
      "resource_name": "ip-172-31-27-101"
    }
  ]
}

Dry Run Output

The output indicates a successful dry run
The operation specified is "NodeAddition," indicating the intent to add a node to the cluster
The resource_name is "ip-172-31-27-101," representing the hostname or identifier for the node being added
Incorrect K8s version - Day 2 operation

Below is an example of the output from the dry run command when a user tries to add an incorrect K8s version:

./rctl apply -f check1.yaml --dry-run
Error: Error performing apply on cluster "mks-test-1-calico": server error [return code: 400]: {"operations":null,"error":{"type":"Processing Error","status":400,"title":"Processing request failed","detail":{"Message":"Kubernetes version v1.28.3 not supported\n"}}}

Dry Run Output

Indicates that an error occurred while trying to apply changes to the cluster named "mks-test-1-calico," and the server returned an HTTP status code 400 (Bad Request).