Attach an existing Mirantis Kubernetes Engine cluster¶

Starting from Mirantis Kubernetes Engine (MKE) 3.3.3, you can attach an existing MKE cluster that is not deployed by Mirantis Container Cloud to a management cluster. This feature allows for visualization of all your MKE clusters details in one place including clusters health, capacity, and usage.

For supported configurations of existing MKE clusters that are not deployed by Container Cloud, see Docker Enterprise Compatibility Matrix.

Using the instruction below, you can also install StackLight to your existing MKE cluster during the attach procedure. For the StackLight system requirements, refer to the Reference Architecture: Requirements of the corresponding cloud provider.

You can also update all your MKE clusters to the latest version once your management cluster automatically updates to a newer version where a new MKE Cluster release with the latest MKE version is available. For details, see Update a managed cluster.

To attach an existing MKE cluster:

1. Log in to the Container Cloud web UI with the writer permissions.

2. Switch to the required project using the Switch Project action icon located on top of the main left-side navigation panel.

3. In the Clusters tab, expand the Create Cluster menu and click Attach Existing MKE Cluster.

4. In the wizard that opens, fill out the form with the following parameters as required:

   1. Configure general settings:

      MKE cluster configuration¶

      Section	Parameter	Description
      General Settings	Cluster Name	Specify the cluster name.
      	Region	Select the required cloud provider: OpenStack, AWS, or bare metal.

   2. Upload the MKE client bundle or fill in the fields manually. To download the MKE client bundle, refer to MKE user access: Download client certificates.

   3. Configure StackLight:

      StackLight configuration¶

      Section	Parameter name	Description
      StackLight	Enable Monitoring	Selected by default. Deselect to skip StackLight deployment. Note You can also enable, disable, or configure StackLight parameters after deploying a managed cluster. For details, see Change a cluster configuration or Configure StackLight.
      	Enable Logging	Select to deploy the StackLight logging stack. For details about the logging components, see Reference Architecture: StackLight deployment architecture.
      	HA Mode	Select to enable StackLight monitoring in the HA mode. For the differences between HA and non-HA modes, see Reference Architecture: StackLight deployment architecture.
      Elasticsearch	Retention Time	The Elasticsearch logs retention period in Logstash.
      	Persistent Volume Claim Size	The Elasticsearch persistent volume claim size.
      Prometheus	Retention Time	The Prometheus database retention period.
      	Retention Size	The Prometheus database retention size.
      	Persistent Volume Claim Size	The Prometheus persistent volume claim size.
      	Enable Watchdog Alert	Select to enable the Watchdog alert that fires as long as the entire alerting pipeline is functional.
      	Custom Alerts	Specify alerting rules for new custom alerts or upload a YAML file in the following exemplary format: - alert: HighErrorRate expr: job:request_latency_seconds:mean5m{job="myjob"} > 0.5 for: 10m labels: severity: page annotations: summary: High request latency For details, see Official Prometheus documentation: Alerting rules. For the list of the predefined StackLight alerts, see Operations Guide: Available StackLight alerts.
      StackLight Email Alerts	Enable Email Alerts	Select to enable the StackLight email alerts.
      	Send Resolved	Select to enable notifications about resolved StackLight alerts.
      	Require TLS	Select to enable transmitting emails through TLS.
      	Email alerts configuration for StackLight	Fill out the following email alerts parameters as required: To - the email address to send notifications to. From - the sender address. SmartHost - the SMTP host through which the emails are sent. Authentication username - the SMTP user name. Authentication password - the SMTP password. Authentication identity - the SMTP identity. Authentication secret - the SMTP secret.
      StackLight Slack Alerts	Enable Slack alerts	Select to enable the StackLight Slack alerts.
      	Send Resolved	Select to enable notifications about resolved StackLight alerts.
      	Slack alerts configuration for StackLight	Fill out the following Slack alerts parameters as required: API URL - The Slack webhook URL. Channel - The channel to send notifications to, for example, #channel-for-alerts.

5. Click Create.

   To view the deployment status, verify the cluster status on the Clusters page. Once the orange blinking dot near the cluster name disappears, the deployment is complete.