使用 docker for mac 从 pod 获取指标

Question

我尝试将Horizontal Pod Autosclaer 用于nginx pod。

当我描述我的 hpa 时，我收到了这条消息 horizontal-pod-autoscaler failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server could not find the requested resource

我使用 docker for mac。不知道会不会有影响

我的部署

apiVersion: apps/v1
kind: Deployment
metadata:
  name: demo-app
spec:
 selector:
   matchLabels:
     run: demo-app
 replicas: 1
 template:
   metadata:
     labels:
       run: demo-app
   spec:
  containers:
    - name: demo-app
      image: my-demo-app:v3
      imagePullPolicy: Never
      resources:
        requests:
          cpu: 250m
        limits:
          cpu: 300m
      ports:
        - containerPort: 80

我的 HPA

apiVersion: autoscaling/v1
kind: HorizontalPodAutoscaler
metadata:
 name: demo-app-hpa
 namespace: default
spec:
 scaleTargetRef:
   apiVersion: apps/v1
   kind: Deployment
   name: demo-app
 minReplicas: 1
 maxReplicas: 3
 targetCPUUtilizationPercentage: 3

kubectl get hpa 命令的输出：

NAME           REFERENCE             TARGETS        MINPODS   MAXPODS   REPLICAS   AGE
demo-app-hpa   Deployment/demo-app   <unknown>/3%   1         3         1          20m

kubectl get --raw /apis/metrics.k8s.io/v1beta1 命令的输出

{"kind":"APIResourceList","apiVersion":"v1","groupVersion":"metrics.k8s.io/v1beta1","resources":[{"name":"nodes","singularName":"","namespaced":false,"kind":"NodeMetrics","verbs":["get","list"]},{"name":"pods","singularName":"","namespaced":true,"kind":"PodMetrics","verbs":["get","list"]}]}

我用this 配置metric-server 但不起作用

Scaling active 设置为 False。我认为这是问题，但我不知道如何改变价值

Answer 1

您好像缺少指标服务器。

Horizo​​ntalPodAutoscaler 通常从一系列聚合 API（metrics.k8s.io、custom.metrics.k8s.io 和 external.metrics.k8s.io）中获取指标。 metrics.k8s.io API 通常由 metrics-server 提供，需要单独启动。有关说明，请参阅metrics-server。 Horizo​​ntalPodAutoscaler 也可以直接从 Heapster 获取指标。

您可以查看kubectl get --raw /apis/metrics.k8s.io/v1beta1是否部署了指标。

要安装metrics-server，只需克隆存储库并运行kubectl create -f deploy/1.8+/

如果您仍有问题，我建议您查看Docker Kubernetes (Mac) - Autoscaler unable to find metrics。