Kubernetes：如何擴展我的 Pod

Question

我是 Kubernetes 的新手。 我嘗試縮放我的豆莢。 首先，我啟動了 3 個 pod：

./cluster/kubectl.sh run my-nginx --image=nginx --replicas=3 --port=80

有開始 3 個豆莢。 首先，我嘗試使用復制控制器來擴大/縮小規模，但這並不存在。 現在似乎是一個副本集。

./cluster/kubectl.sh get rs
NAME                  DESIRED   CURRENT   AGE
my-nginx-2494149703   3         3         9h

我嘗試更改副本集中描述的副本數量：

./cluster/kubectl.sh scale --replicas=5 rs/my-nginx-2494149703
replicaset "my-nginx-2494149703" scaled

但我仍然看到我的 3 個原始豆莢

./cluster/kubectl.sh get pods
NAME                        READY     STATUS    RESTARTS   AGE
my-nginx-2494149703-04xrd   1/1       Running   0          9h
my-nginx-2494149703-h3krk   1/1       Running   0          9h
my-nginx-2494149703-hnayu   1/1       Running   0          9h

我希望看到 5 個豆莢。

./cluster/kubectl.sh describe rs/my-nginx-2494149703
Name:       my-nginx-2494149703
Namespace:  default
Image(s):   nginx
Selector:   pod-template-hash=2494149703,run=my-nginx
Labels:     pod-template-hash=2494149703
        run=my-nginx
Replicas:   3 current / 3 desired
Pods Status:    3 Running / 0 Waiting / 0 Succeeded / 0 Failed

為什么不擴大規模？ 我是否還必須更改部署中的某些內容？

當我在擴展后描述我的 rs 時，我看到了類似的東西：（在這里我嘗試從一個正在運行的 pod 擴展到 3 個正在運行的 pod）。 但它仍然是一個正在運行的吊艙。 其他 2 個立即啟動並終止

  34s       34s     1   {replicaset-controller }            Normal      SuccessfulCreate    Created pod: my-nginx-1908062973-lylsz
  34s       34s     1   {replicaset-controller }            Normal      SuccessfulCreate    Created pod: my-nginx-1908062973-5rv8u
  34s       34s     1   {replicaset-controller }            Normal      SuccessfulDelete    Deleted pod: my-nginx-1908062973-lylsz
  34s       34s     1   {replicaset-controller }            Normal      SuccessfulDelete    Deleted pod: my-nginx-1908062973-5rv8u

Answer 1

這對我有用

kubectl scale --replicas=<expected_replica_num> deployment <deployment_label_name>

示例

# kubectl scale --replicas=3 deployment xyz

Answer 2

TL;DR：您需要擴展部署而不是直接擴展副本集。

如果您嘗試擴展副本集，那么它將（在很短的時間內）有一個新的計數為 5。但是部署控制器將看到副本集的當前計數為 5，並且因為它知道它應該是為 3，它會將其重置為 3。通過手動修改為您創建的副本集，您正在與系統控制器作斗爭（這是不倦的，並且幾乎總是比您更持久）。

Answer 3

kubectl run my-nginx --image=nginx --replicas=3 --port=80在這個kubectl run中將創建一個部署或作業來管理創建的容器。
Deployment-->ReplicaSet-->Pod這就是 kubernetes 的工作方式。
如果您更改底層對象，則其更高級別的對象將撤消您的更改。您必須更改頂層對象。

Answer 4

將其縮小到零，然后縮小到您需要的 pod 數量（猜它等於 3）

kubectl scale deployment <deployment-name> --replicas=0 -n <namespace>
kubectl scale deployment <deployment-name> --replicas=3 -n <namespace>

Answer 5

下面的例子展示了你應該如何擴大/縮小你的“pods/resource/deployments”。

k8smaster@k8smaster:~/debashish$ more createdeb_deployment1.yaml 


--- 
apiVersion: apps/v1beta2
kind: Deployment
metadata: 
  name: debdeploy-webserver
spec: 
  replicas: 1
  selector: 
    matchLabels: 
      app: debdeploy1webserver
  template: 
    metadata: 
      labels: 
        app: debdeploy1webserver
    spec: 
      containers: 
        - 
          image: "docker.io/debu3645/debapachewebserver:v1"
          name: deb-deploy1-container 
          ports: 
            - 
              containerPort: 6060

部署已創建-->

**kubectl -n debns1 create -f createdeb_deployment1.yaml**




k8smaster@k8smaster:~/debashish$ `kubectl scale --replicas=5 **deployment**/debdeploy-webserver -n debns1`

（擴展 5 個部署）

k8smaster@k8smaster:~/debashish$ kubectl get pods -n debns1


NAME                                   READY   STATUS    RESTARTS   AGE
debdeploy-webserver-7cf4fb74c5-8wvzx   1/1     Running   0          16s
debdeploy-webserver-7cf4fb74c5-jrf6v   1/1     Running   0          16s
debdeploy-webserver-7cf4fb74c5-m9fpw   1/1     Running   0          16s
debdeploy-webserver-7cf4fb74c5-q9n7r   1/1     Running   0          16s
debdeploy-webserver-7cf4fb74c5-ttw6p   1/1     Running   1          19h
resourcepod-deb1                       1/1     Running   5          6d18h




k8smaster@k8smaster:~/debashish$ **kubectl get ep -n debns1**



NAME                ENDPOINTS                                                     AGE
frontend-svc-deb    192.168.1.10:80,192.168.1.11:80,192.168.1.12:80 + 2 more...   18h
frontend-svc1-deb   192.168.1.8:80                                                14d
frontend-svc2-deb   192.168.1.8:80                                                5d19h




k8smaster@k8smaster:~/debashish$ **kubectl scale --replicas=2** deployment/debdeploy-webserver -n debns1 

（從 5 縮小到 2 ）

deployment.extensions/debdeploy-webserver 縮放

k8smaster@k8smaster:~/debashish$ **kubectl get pods -n debns1**


NAME                                   READY   STATUS        RESTARTS   AGE
debdeploy-webserver-7cf4fb74c5-8wvzx   1/1     Terminating   0          35m
debdeploy-webserver-7cf4fb74c5-jrf6v   1/1     Terminating   0          35m
debdeploy-webserver-7cf4fb74c5-m9fpw   1/1     Terminating   0          35m
debdeploy-webserver-7cf4fb74c5-q9n7r   1/1     Running       0          35m
debdeploy-webserver-7cf4fb74c5-ttw6p   1/1     Running       1          19h
resourcepod-deb1                       1/1     Running       5          6d19h


k8smaster@k8smaster:~/debashish$ **kubectl get pods -n debns1**


NAME                                   READY   STATUS    RESTARTS   AGE
debdeploy-webserver-7cf4fb74c5-q9n7r   1/1     Running   0          37m
debdeploy-webserver-7cf4fb74c5-ttw6p   1/1     Running   1          19h
resourcepod-deb1                       1/1     Running   5          6d19h

k8smaster@k8smaster:~/debashish$ kubectl **scale --current-replicas=4 --replicas=2** deployment/debdeploy-webserver -n debns1  (Check the current no. of deployments. If current replication is 4, then bring it down to 2, else dont do anything)


error: Expected replicas to be 4, was 2


k8smaster@k8smaster:~/debashish$ **kubectl scale --current-replicas=3 --replicas=10 deployment/debdeploy-webserver -n debns1**


error: Expected replicas to be 3, was 2


k8smaster@k8smaster:~/debashish$ **kubectl scale --current-replicas=2 --replicas=10 deployment/debdeploy-webserver -n debns1**

deployment.extensions/debdeploy-webserver 縮放

k8smaster@k8smaster:~/debashish$ **kubectl get pods -n debns1**


    NAME                                   READY   STATUS              RESTARTS   AGE
    debdeploy-webserver-7cf4fb74c5-46bxg   1/1     Running             0          6s
    debdeploy-webserver-7cf4fb74c5-d6qsx   0/1     ContainerCreating   0          6s
    debdeploy-webserver-7cf4fb74c5-fdq6v   1/1     Running             0          6s
    debdeploy-webserver-7cf4fb74c5-gd87t   1/1     Running             0          6s
    debdeploy-webserver-7cf4fb74c5-kqdbj   0/1     ContainerCreating   0          6s
    debdeploy-webserver-7cf4fb74c5-q9n7r   1/1     Running             0          47m
    debdeploy-webserver-7cf4fb74c5-qjvm6   1/1     Running             0          6s
    debdeploy-webserver-7cf4fb74c5-skxq4   0/1     ContainerCreating   0          6s
    debdeploy-webserver-7cf4fb74c5-ttw6p   1/1     Running             1          19h
    debdeploy-webserver-7cf4fb74c5-wlc7q   0/1     ContainerCreating   0          6s
    resourcepod-deb1                       1/1     Running             5          6d19h

Answer 6

不確定這是否是我開始使用 kubernetes 的最佳方式，但我通過更新我的 yaml 文件來做到這一點

# app.yaml
apiVersion: apps/v1
...
spec:
  replicas: <new value>

並運行$ kubectl scale -f app.yaml --replicas=<new value>

你可以通過運行$ kubectl get pods來驗證你的新副本數量

就我而言，我也有興趣在谷歌雲上縮減我的虛擬機。 我這樣做了$ gcloud container clusters resize appName --size=1 --zone "my-zone"