Enterprise Distributed Application Service:Configure virtual nodes for a Kubernetes application

Limits

This feature is applicable only to ACK Managed Edition or ACK dedicated clusters that run Kubernetes 1.14 or later.

Schedule an EDAS application to virtual nodes

Method 1: Configure a pod tag

When you create or deploy an application in Enterprise Distributed Application Service (EDAS), set Label Configuration in the Advanced Settings step by setting Name to alibabacloud.com/eci and Value to true. Then, the pods of the application are scheduled to virtual nodes.

Method 2: Configure a namespace tag

Add the tag alibabacloud.com/eci=true to a Kubernetes cluster namespace. Then, new pods are scheduled to virtual nodes. This does not affect the pods that are already running.

Method 3: Configure ECI-based scheduling

When you create or deploy an application in EDAS, set Annotation Configuration in the Advanced Settings step by setting Name to alibabacloud.com/burst-resource and Value to one of the following options:

• eci: Elastic container instances are used when the resources on the real nodes of the cluster are insufficient.
• eci_only: Only elastic container instances are used.

Method 4: Configure priority-based resource scheduling

Configure Elastic Compute Service (ECS) and ECI hybrid scheduling for the Kubernetes application in EDAS with the application ID 933ff653-xxxx-xxxx-xxxx-d127a75cxxxx. When the resources on the real ECS nodes of the cluster are insufficient, pods are scheduled to virtual nodes.

apiVersion: scheduling.alibabacloud.com/v1alpha1
kind: ResourcePolicy
metadata:
  name: edas-app-name // We recommend that you use the same name as the application in EDAS.
  namespace: edas-app-namespace // Use the same namespace as the application in EDAS.
spec:
  selector:
    edas.appid: 933ff653-xxxx-xxxx-xxxx-d127a75cxxxx
  strategy: prefer
  units:
  - resource: ecs
  - resource: eci

Method 5: Use virtual-kubelet-autoscaler to schedule pods to elastic container instances

virtual-kubelet-autoscaler is a Kubernetes Autoscaler plug-in that is provided by Alibaba Cloud. If no matching node is available during pod scheduling (for example, if existing ECS work nodes are insufficient), virtual-kubelet-autoscaler will function and reschedule the pods that failed to be scheduled to elastic container instances (virtual nodes).

For more information about how to install the plug-in, see Install virtual-kubelet-autoscaler.

Method 6: Configure Elastic Container Instance Profile

Modify the ConfigMap that is named eci-profile in the kube-system namespace of the Kubernetes cluster.

Configure Elastic Container Instance Profile for the Kubernetes application whose application ID is 933ff653-xxxx-xxxx-xxxx-d127a75cxxxx. This configuration schedules the pods of the application to elastic container instances, automatically enables the image cache feature, and adds the created-by-eci label whose value is true.

apiVersion: v1
kind: ConfigMap
metadata:
  name: eci-profile
  namespace: kube-system
data:
  vpcId: "vpc-xxx"
  securityGroupId: "sg-xxx"
  vswitchIds: "vsw-111,vsw-222"
  enableClusterIp: "true"
  enableHybridMode: "false"
  enablePrivateZone: "false"
  selectors: |
    [
        {
            "name":"for-edas-app-1",
            "objectSelector":{
                "matchLabels":{
                    "edas.appid": 933ff653-xxxx-xxxx-xxxx-d127a75cxxxx
                }
            },
            "effect":{  # The annotations and labels to be added.
                "annotations":{
                    "k8s.aliyun.com/eci-image-cache": "true"
                },
                "labels":{
                    "created-by-eci":"true"
                }
            }
        }
    ]

For more information, see Configure Elastic Container Instance Profile.