Create and manage cluster

This guide explains how to create, manage, and update Kubernetes Engine clusters.

Create cluster

A cluster is the fundamental resource of Kubernetes Engine, where all Kubernetes objects including container applications are run.

info

• You can operate clusters and nodes across multiple availability zones (AZs) in multi-AZ-supported regions to improve availability.
• To create a cluster, VPC and subnets must be preconfigured. If not, refer to Create and manage VPC.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.

2. Select the [Start] button to begin using Kubernetes Engine.

   • When the service starts, a Service Agent is automatically created to access Kubernetes Engine resources.

3. In the Cluster menu, select the [Create cluster] button.

4. In the Create cluster window, enter the required information and select [Create].

   

   Category	Description
   Basic settings	• Set basic cluster information - Cluster name: Enter the cluster name - Cluster description (optional): Up to 60 characters - Kubernetes version: Choose the Kubernetes version for the cluster   ㄴ For details on supported versions, refer to Support information
   Cluster network settings	• Configure network settings - VPC: Select the VPC to deploy the cluster - Subnet: Select the subnet to deploy the cluster   ㄴ When creating a node pool, choose from the subnets configured in the cluster network   ㄴ In multi-AZ environments, select multiple subnets across different AZs to improve availability   ㄴ For multi-AZ clusters, select at least one subnet per AZ • Cluster endpoint access: Choose public or private endpoint   ㄴ Public: API server accessible from the internet   ㄴ Private: API server accessible only within the VPC
   CNI	• Choose a CNI plugin for the cluster: Calico or Cilium - Service IP CIDR block (optional): IP range for service objects - Pod IP CIDR block (optional): IP range for pods ⚠️ Caution Service and Pod IPs cannot be changed after cluster creation.

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If the cluster network is in a private subnet, internet communication is not available.
Use a NAT instance to allow outbound access for nodes in a private subnet.
See Using NAT instance for more.

caution

The following conditions apply to service and pod IPs for CNIs:

• Must be in CIDR format and within the RFC-1918 private IPv4 range.
• Minimum /28 and maximum /12 for service IPs.
• Minimum /24 and maximum /16 for pod IPs.
• Service and pod IPs must not overlap.
• Must not overlap with VPC IP ranges.
• Must not overlap with internal range 198.18.0.0/16 used by Kubernetes Engine.
• Only IPv4 is supported.

Cluster endpoint

• The cluster API server endpoint URL is based on the access option.

  Option	Behavior
  Public cluster endpoint	Provides a publicly accessible API server endpoint with a public IP.
  Private cluster endpoint	Provides a private API server endpoint accessible only within the VPC.

Endpoint access control

When creating a cluster, you can specify the IPv4 CIDR ranges that can access the API server endpoint.

Setting	Description
Allow all	Allow network access to the cluster API server endpoint from all IPv4 addresses (0.0.0.0/0)
Specify allowlist	Allow access only from addresses registered in the allowed CIDR block list. You can register 1-40 CIDR blocks and enter a description of up to 10 characters for each block

caution

If the allowlist does not include your current IP address, you cannot access the cluster API server endpoint. If you cannot determine your current IP address, enter the CIDR block to allow directly.

Tutorial

After creating a cluster, see the following tutorials for operational setup expansion.

• Deploy Kubernetes cluster with Kubernetes Engine: Basic deployment flow
• Integrate Kubernetes cluster with object storage: Application storage integration
• Use NVIDIA GPU worker nodes in Kubernetes Engine clusters: GPU workload runtime setup

Manage cluster

Here’s how to manage clusters in Kubernetes Engine.

View cluster list

You can view the list of existing clusters.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.

2. In the Cluster menu, view the created clusters.

   Category	Description
   Name	Cluster name
   ID	Unique cluster ID
   Status	Cluster status - Provisioned: Provisioning complete - Pending: Preparing to provision - Provisioning: Provisioning in progress - Deleting: Being deleted - Failed: Requires user intervention
   Kubernetes version	Current version
   Creator	ID of the user who created the cluster
   Created at	Cluster creation date
   [More] icon	- Change description: Change the cluster description - kubeconfig file: Download the kubeconfig file for kubectl - Configure endpoint access control: Configure CIDR ranges that can access the cluster API server endpoint - Create node pool: Create a node pool in the cluster - Delete: Delete the cluster

View cluster details

You can view cluster details and information about topology, networks, endpoint access control, node pools, and nodes.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.

2. In the Cluster menu, select the cluster whose details you want to view.

3. View information on each tab of the cluster details page.

   Tab	Description
   Details	View basic cluster information and resource status
   Topology	View the cluster subnet, node pool, and node configuration
   Network	View the VPC and subnet information used by the cluster
   Endpoint access control	View the access range allowed for the cluster API server endpoint
   Node pool	View node pool information for the cluster
   Node	View node information for the cluster

View cluster details tab

You can view basic cluster information and resource status.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.

2. In the Cluster menu, select the cluster whose details you want to view.

3. View the information on the Details tab.

   Category	Description
   Name	Cluster name
   ID	Unique cluster ID
   Status	Current cluster status
   Kubernetes version	Kubernetes version currently in use
   API server endpoint	Endpoint used to call the cluster API
   CNI	CNI plugin used by the cluster
   Service CIDR block	IP address range assigned to cluster Services
   Pod CIDR block	IP address range assigned to Pods
   Node pools	Number of node pools in the cluster
   Nodes	Number of nodes in the cluster
   Total vCPU	Total vCPU count of worker nodes in the cluster
   Total memory	Total memory of worker nodes in the cluster
   Creator ID	ID of the user who created the cluster
   Created at	Date and time when the cluster was created

View node pool information

You can view the node pools in the cluster and the nodes in each pool.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.
2. In the Cluster menu, select the cluster whose node pool information you want to view.
3. Click the Node pool tab, and then view the information.

View node information

You can view information about all nodes in the cluster.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.
2. In the Cluster menu, select the cluster whose node information you want to view.
3. Click the Node tab, and then view the information.

Change cluster description

You can change the cluster description.

1. In the KakaoCloud console, go to Kubernetes Engine.
2. In the Cluster menu, click [⋮] for the cluster, and then select Change description.
3. Change the description, and then click [Change].

Configure endpoint access control

You can change the allowed access range of the API server endpoint after creating a cluster.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.
2. In the Cluster menu, click [⋮] for the cluster, and then select Configure endpoint access control.
3. Select Allow all or Specify allowlist.
4. If you select Specify allowlist, enter the allowed CIDR blocks and descriptions, and then click [Save].

For input requirements and precautions, see Endpoint access control.

Delete cluster

Delete unused clusters.

caution

• Deleting a cluster also deletes the resources created automatically with it. See Automatically generated resources.
• If non-node resources are attached to auto-created security groups, those groups are not deleted.

1. Go to Kubernetes Engine in the KakaoCloud console.
2. In the Cluster menu, select the [More] icon and select Delete cluster.
3. Enter required info in the popup and select [Delete].

Update cluster

If a newer Kubernetes version is available, you can update the control plane of your cluster.

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Refer to Support information for supported versions.

Before starting update

Make sure all update conditions are met. Otherwise, the update cannot proceed.
Review the Kubernetes changelogs for application impact.

Update conditions

Condition	Description
Cluster status	Must be Provisioned
Node pool status	All must be Running
Node pool version	Must match the cluster version exactly

Update procedures

If the cluster is eligible, perform the update:

info

Kubernetes supports sequential version updates. You can only update one version at a time.

caution

Updates cannot be canceled or rolled back once started.

1. Go to KakaoCloud console > Container Pack > Kubernetes Engine.
2. In the Cluster menu, select the [Update] button next to the Kubernetes version.
3. In the popup, confirm the version and select [Update].
4. The cluster status changes to Updating and reverts to Provisioned after completion. Node pool settings are locked during the update.

Considerations after updating

New node pools will use the latest cluster version.
Existing node pools must be updated. See Update nodes.

What to check if an update fails

If an update fails, the cluster status changes to Failed.
Contact Helpdesk > Technical Inquiry.

1. In the KakaoCloud console, go to Helpdesk (top-right).
2. In the Q&A tab, select [Ask a question].
3. Select Technical Inquiry.
4. Fill in the form and select [Submit].