水平Pod自动缩放目标显示/50%，带有“kubectl get hpa”

Question

尝试将自动缩放部署到我的集群，但目标显示为“未知”，我尝试了不同的指标服务器，但无济于事。我关注了[这个githhub问题]（https“//github.com/kubernetes/minikube/issues4456/）甚至认为我使用的是Kubeadm而不是迷你库贝，它并没有改变问题。

我也关注了这个堆栈帖子，但也没有成功。

我正在运行Ubuntu 20.0.4 LTS。

使用 kubernetes version 1.23.5， for kubeadm ，kubcectl， ect

按照另一个stack帖子的建议，我通过curl获得了最新版本

<代码>卷曲-Lhttps://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml

我将文件编辑如下：

    spec:
      containers:
      - args:
        - --cert-dir=/tmp
        - --secure-port=4443
        - --kubectl-insecure-tls
        - --kubelet-preferred-address-types=InternalIP
        - --kubelet-use-node-status-port
        - --metric-resolution=15s
        image: k8s.gcr.io/metrics-server/metrics-server:v0.6.1
        imagePullPolicy: IfNotPresent

然后我运行了kubectl apply -f components.yaml

仍然不起作用:

$kubectl获取hpa名称参考目标MINPODS MAXPODS REPLICAS AGE teastore-webui-hpa部署/teastore-webui

另一个建议是明确声明限制。

$ kubectl autoscale deployment teastore-webui --max=20 --cpu-percent=50 --min=1
horizontalpodautoscaler.autoscaling/teastore-webui autoscaled
 
group8@group8:~/Downloads/TeaStore-master/examples/kubernetes$ kubectl get hpa
NAME                 REFERENCE                   TARGETS         MINPODS   MAXPODS   REPLICAS   AGE
teastore-webui       Deployment/teastore-webui   <unknown>/50%   1         20        0          4s
teastore-webui-hpa   Deployment/teastore-webui   <unknown>/50%   1         20        1          20h

这也没有奏效。

这是我尝试自动缩放的部署和服务配置的一个应用。

    spec:
      containers:
        - name: teastore-webui
          image: descartesresearch/teastore-webui
          ports:
            - containerPort: 8080
          env:
            - name: HOST_NAME
              value: "teastore-webui"
            - name: REGISTRY_HOST
              value: "teastore-registry"
          resources:
            requests:
              cpu: "250m"
---
apiVersion: autoscaling/v2beta2
kind: HorizontalPodAutoscaler
metadata:
  name: teastore-webui-hpa
  labels:
    app: teastore
spec:
  maxReplicas: 20
  minReplicas: 1
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: teastore-webui
  metrics:
    - type: Resource
      resource:
        name: cpu
        target:
          type: Utilization
          averageUtilization: 50
---
apiVersion: v1
kind: Service
metadata:
  name: teastore-webui
  labels:
    app: teastore
    run: teastore-webui
spec:
  type: NodePort
  ports:
    - port: 8080
      nodePort: 30080
      protocol: TCP
  selector:
    run: teastore-webui

根据其他建议，我将资源明确声明为cpu，利用率为50%，cpu请求设置为250 milicores。

   $kubectl describe hpa
Warning: autoscaling/v2beta2 HorizontalPodAutoscaler is deprecated in v1.23+, unavailable in v1.26+; use autoscaling/v2 HorizontalPodAutoscaler
Name:                                                  teastore-webui
Namespace:                                             default
Labels:                                                <none>
Annotations:                                           <none>
CreationTimestamp:                                     Sat, 02 Apr 2022 16:07:25 -0400
Reference:                                             Deployment/teastore-webui
Metrics:                                               ( current / target )
  resource cpu on pods  (as a percentage of request):  <unknown> / 50%
Min replicas:                                          1
Max replicas:                                          20
Deployment pods:                                       1 current / 0 desired
Conditions:
  Type           Status  Reason                   Message
  ----           ------  ------                   -------
  AbleToScale    True    SucceededGetScale        the HPA controller was able to get the target's current scale
  ScalingActive  False   FailedGetResourceMetric  the HPA was unable to compute the replica count: failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server is currently unable to handle the request (get pods.metrics.k8s.io)
Events:
  Type     Reason                        Age                    From                       Message
  ----     ------                        ----                   ----                       -------
  Warning  FailedComputeMetricsReplicas  29m (x12 over 32m)     horizontal-pod-autoscaler  invalid metrics (1 invalid out of 1), first error is: failed to get cpu utilization: unable to get metrics for resource cpu: unable to fetch metrics from resource metrics API: the server is currently unable to handle the request (get pods.metrics.k8s.io)
  Warning  FailedGetResourceMetric       2m12s (x121 over 32m)  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 is currently unable to handle the request (get pods.metrics.k8s.io)

Answer 1

这个yaml第6行的语法错误。它需要--kubelet不安全tls，而不是--kubectl不安全tls

spec:
  containers:
  - args:
    - --cert-dir=/tmp
    - --secure-port=4443
    - --kubectl-insecure-tls
    - --kubelet-preferred-address-types=InternalIP
    - --kubelet-use-node-status-port
    - --metric-resolution=15s
    image: k8s.gcr.io/metrics-server/metrics-server:v0.6.1
    imagePullPolicy: IfNotPresent

通过检查日志文件注意到

kubectl logs -f metric-server -n kube-system

谢谢大卫·麦子的评论。