A managed edge Kubernetes cluster must contain at least one Elastic Compute Service (ECS) instance. This topic describes how ECS instances work and how to add or remove ECS instances.
Cloud management nodes in edge computing

When you create a managed edge cluster, ACK@Edge automatically creates at least one
ECS instance as a cloud management node for the cluster. This ECS instance is used
to run cloud management applications. You can deploy custom cloud management applications.
The taint node-role.alibabacloud.com/addon: Effect: NoSchedule is automatically added to a cloud management node to prevent edge workloads from
being scheduled to the node. By default, a management node of version 1.14.8-aliyunedge.1
or earlier has the following management applications:
- alibaba-log-controller: the Log Service controller.
- alicloud-monitor-controller: the CloudMonitor controller.
- metric-server: the server that is used to monitor the cluster.
- edge-tunnel-server: the server for the reverse O&M tunnel. It allows you to use the native Kubernetes API to access edge nodes, monitor containers, and use SSH to remotely run commands.
Deploy applications to cloud management nodes
If you want to deploy custom management applications on cloud management nodes, for
example, to deploy different types of operators, you must specify a toleration that
matches the preceding taint and configure node selectors. The following example describes
how to set the parameters.
...
nodeSelector:
alibabacloud.com/is-edge-worker: 'false'
beta.kubernetes.io/arch: amd64
beta.kubernetes.io/os: linux
tolerations:
- effect: NoSchedule
key: node-role.alibabacloud.com/addon
operator: Exists
...
Add a cloud management node
To add a cloud management node, perform the following steps. ACK@Edge will support ECS-based auto scaling in later versions.