Container Service for Kubernetes:FAQ about registered clusters

Is there a charge for registered clusters?

Registered clusters are free of charge. Other cloud resources you use alongside them — such as Elastic Compute Service (ECS) instances or elastic container instances — are billed separately. For pricing details, see Overview of registered clusters.

Can I use Alibaba Cloud resources to scale out an on-premises cluster?

Yes. You can add Alibaba Cloud resources to an on-premises cluster by granting the registered cluster permissions on your applications. For a step-by-step guide, see Build a hybrid cloud cluster and add ECS instances to the cluster.

What network access does the cluster registration proxy require?

The cluster registration proxy exposes two endpoints: a public endpoint and an internal endpoint.

Internal endpoint required: Register the external cluster using the internal endpoint in these scenarios:

• Adding ECS instances or ECS bare metal instances via the node pool feature. See Build a hybrid cloud cluster and add ECS instances to the cluster.

• Deploying elastic container instances using the ack-virtual-node component. See Deploy the virtual node controller and use it to create Elastic Container Instance-based pods.

Port requirement: Make sure the external cluster can reach the cluster registration proxy endpoint on port 5533. See Functions and features.

Other features — cluster management, security management, logs, and monitoring and alerting — do not require internal network connectivity. These features only need Internet access.

To enable Internet access for the cluster API server using an elastic IP address (EIP), see Control public access to the API server of a cluster.

Node resource quotas and usage are missing on the Nodes page — how do I fix this?

The ACK console uses the metrics-server component to collect node resource quotas and usage. If this data is missing, metrics-server is either not installed or has a compatibility issue.

Check whether metrics-server is installed: Go to the Add-ons page in the ACK console and look for metrics-server. If it is not listed as installed, install it from that page. See Manage components.

If a third-party metrics-server is already installed: A pre-existing open source or third-party metrics-server component can cause compatibility issues that prevent node data from appearing. Delete the existing component, then install the metrics-server provided by ACK from the Add-ons page.

The ACK metrics-server is a resource monitoring tool that ACK develops based on the open source Metrics Server. It collects resource usage metrics for all pods in your cluster and enables the Horizontal Pod Autoscaler (HPA) to scale workloads based on those metrics. For details, see metrics-server.