This topic describes how to scale out the worker nodes in a cluster in the Container Service for Kubernetes console.

Background information

Master nodes cannot be scaled out in a cluster.


  1. Log on to the ACK console.
  2. In the left-side navigation pane, click Clusters.
  3. On the Clusters page, find the cluster that you want to expand and select Expand from the More drop-down list in the Actions column.
  4. On the Expand page, set the scale-out parameters.
    The following table describes the required parameters.
    Parameter Description
    Region The region where the cluster is deployed.
    Container Runtime The default runtime is Docker 19.03.5.
    VPC Set the network for the nodes. You can select a Virtual Private Cloud (VPC) network from the drop-down list. If no VPC network is available, click Create VPC. For more information, see Create a VPC.
    VSwitch Select one or more VSwitches for the cluster.

    You can select up to three VSwitches deployed in different zones. If no VSwitch is available, you can click Create VSwitch to create one. For more information, see Create a VSwitch.

    Billing Method The pay-as-you-go and subscription billing methods are supported. For more information, see Comparison of billing methods. If you select the subscription billing method,
    • set the Duration parameter. Duration: You can select 1, 2, 3, or 6 months. If you require a longer duration, you can select 1 to 5 years.
    • Specify whether to enable Auto Renewal.
    Instance Type You can select one or more instance types. For more information, see Instance families.
    Selected Types The specified instance types appear here.
    System Disk
    ESSDs, SSDs, and ultra disks are supported.
    Note You can select Enable Backup to back up disk data.
    Mount Data Disk

    ESSDs, SSDs, and ultra disks are supported. You can enable disk encryption and backup when you add data disks.

    Nodes to Add The number of nodes to be added to the cluster. You can add up to 100 nodes to a cluster for the current account. You can add up to 500 nodes at a time.
    Logon Type
    • Key Pair:
      • Key Pair: Select an SSH key pair from the drop-down list.
      • create a key pair: Create a key pair if no SSH key pair is available. For more information about how to create an SSH key pair, see Create an SSH key pair. After the key pair is created, set it as the credential for logging on to the cluster.
    • Password:
      • Password: Enter a password for logging on to the nodes.
      • Confirm Password: Enter the password again.
    ECS Label You can attach labels to the selected ECS instances.
    Node Label You can attach labels to the nodes of the cluster.
    Taints Add taints to all worker nodes in the cluster.
    Custom Image
    You can select a custom image, and then use the image to deploy all nodes in the cluster. For more information about how to create a custom image, see Create a Kubernetes cluster by using a custom image.
    Note This feature is available to only users in the whitelist. If you are not in the whitelist, submit a ticket.
    RDS Whitelist Set the Relational Database Service (RDS) whitelist. Add the IP addresses of cluster nodes to the RDS whitelist.
    Note To enable an RDS instance to access a Kubernetes cluster, you must deploy the RDS instance in the same VPC network as the Kubernetes cluster.
    User Data For more information, see Prepare user data.
  5. Click OK.
    On the Node Pools page, Scaling appears in the Status column of the node pool. This indicates that the scale-out event is in progress. After the scale-out event is completed, the Status column of the node pool changes to Active.

What to do next

Click Details in the Actions column of the node pool. On the Nodes tab, you can check the nodes that are added to the node pool of the cluster.