Limits

Overview

Before you use ACK, take note of the following limits:

• You must pass real-name verification before you can create an ACK cluster.
• You cannot perform the following operations on ACK clusters after the clusters are created:
  • Change the virtual private cloud (VPC).
  • Change a managed Kubernetes cluster to a dedicated Kubernetes cluster, or change a professional managed Kubernetes cluster to a standard managed Kubernetes cluster.
  • Change the network plug-in.
  • Change the volume plug-in.
  • Migrate applications across namespaces.
• The following limits apply to Elastic Compute Service (ECS) instances in ACK clusters:
  • ECS instances support the pay-as-you-go and subscription billing methods. Other resources, such as Server Load Balancer (SLB) instances, support only the pay-as-you-go billing method. You can change the billing method from pay-as-you-go to subscription in the ECS console.
  • When you create clusters, expand clusters, or perform auto scaling of clusters, you may fail to create nodes due to resource quota limits or inventory availability.
  • If you want to create subscription ECS instances when you create a cluster, you may fail to create the ECS instances due to resource quota limits or inventory availability. After a subscription ECS instance is created, you cannot release the ECS instance before the subscription expires.
    Note To avoid these issues, we recommend that you create pay-as-you-go ECS instances when you create a cluster. You can change the billing method from pay-as-you-go to subscription in the ECS console based on your requirements.
  • Requirements for ECS specifications: You must select ECS instances with at least 4 vCPUs and 8 GiB of memory.
• Bandwidth limits on access to the control plane components:

  Bandwidth limits apply when you access the control pane components, including kube-apiserver and etcd, of a cluster by calling API operations or by using command lines. If you read a large number of cluster events at a time, bandwidth throttling may be triggered and you may fail to read the events. We recommend that you query cluster events in the event center. Alternatively, you can add paging parameters, such as --chunk-size=500, to the API request or command lines to reduce the number of events to be read. If bandwidth throttling is frequently triggered in a standard managed Kubernetes cluster, you can migrate workloads from the cluster to a professional managed Kubernetes cluster.

  For more information about the event center, see Scenario 1: Use node-problem-detector with the Kubernetes event center of Log Service to sink cluster events.

  For more information about how to migrate workloads from a standard managed Kubernetes cluster to a professional managed Kubernetes cluster, see Hot migration from standard managed Kubernetes clusters to professional managed Kubernetes clusters.

Quota limits

Quota limits on underlying cloud resources