一滚动升级

根据资源编排文件部署一个Nginx应用，指定其版本为1.14，副本数为2个，对其升级为1.15，这个资源描述文件可以生成，然后修改副本数和nginx版本

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    deployment.kubernetes.io/revision: "1"
  creationTimestamp: "2021-05-26T14:05:03Z"
  generation: 1
  labels:
    app: web
  managedFields:
  - apiVersion: apps/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:labels:
          .: {}
          f:app: {}
      f:spec:
        f:progressDeadlineSeconds: {}
        f:replicas: {}
        f:revisionHistoryLimit: {}
        f:selector:
          f:matchLabels:
            .: {}
            f:app: {}
        f:strategy:
          f:rollingUpdate:
            .: {}
            f:maxSurge: {}
            f:maxUnavailable: {}
          f:type: {}
        f:template:
          f:metadata:
            f:labels:
              .: {}
              f:app: {}
          f:spec:
            f:containers:
              k:{"name":"nginx"}:
                .: {}
                f:image: {}
                f:imagePullPolicy: {}
                f:name: {}
                f:resources: {}
                f:terminationMessagePath: {}
                f:terminationMessagePolicy: {}
            f:dnsPolicy: {}
            f:restartPolicy: {}
            f:schedulerName: {}
            f:securityContext: {}
            f:terminationGracePeriodSeconds: {}
    manager: kubectl
    operation: Update
    time: "2021-05-26T14:05:03Z"
  - apiVersion: apps/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          .: {}
          f:deployment.kubernetes.io/revision: {}
      f:status:
        f:availableReplicas: {}
        f:conditions:
          .: {}
          k:{"type":"Available"}:
            .: {}
            f:lastTransitionTime: {}
            f:lastUpdateTime: {}
            f:message: {}
            f:reason: {}
            f:status: {}
            f:type: {}
          k:{"type":"Progressing"}:
            .: {}
            f:lastTransitionTime: {}
            f:lastUpdateTime: {}
            f:message: {}
            f:reason: {}
            f:status: {}
            f:type: {}
        f:observedGeneration: {}
        f:readyReplicas: {}
        f:replicas: {}
        f:updatedReplicas: {}
    manager: kube-controller-manager
    operation: Update
    time: "2021-05-26T14:05:19Z"
  name: web
  namespace: default
  resourceVersion: "92795"
  selfLink: /apis/apps/v1/namespaces/default/deployments/web
  uid: f7d3da76-4493-4288-b3a8-ef724c0a739c
spec:
  progressDeadlineSeconds: 600
  replicas: 2
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: web
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: web
    spec:
      containers:
      - image: nginx:1.14
        imagePullPolicy: Always
        name: nginx
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      terminationGracePeriodSeconds: 30
status:
  availableReplicas: 1
  conditions:
  - lastTransitionTime: "2021-05-26T14:05:19Z"
    lastUpdateTime: "2021-05-26T14:05:19Z"
    message: Deployment has minimum availability.
    reason: MinimumReplicasAvailable
    status: "True"
    type: Available
  - lastTransitionTime: "2021-05-26T14:05:03Z"
    lastUpdateTime: "2021-05-26T14:05:19Z"
    message: ReplicaSet "web-5dcb957ccc" has successfully progressed.
    reason: NewReplicaSetAvailable
    status: "True"
    type: Progressing
  observedGeneration: 1
  readyReplicas: 1
  replicas: 1
  updatedReplicas: 1

使用这个资源编排文件生成应用 web

[root@k8smaster ~]# kubectl apply -f web.yaml
[root@k8smaster ~]# kubectl get pods
NAME                   READY   STATUS    RESTARTS   AGE
web-66bf4959f5-kfktx   1/1     Running   0          76s
web-66bf4959f5-mflm9   1/1     Running   0          76s
# 滚动升级到1.15
[root@k8smaster ~]# kubectl set image deploy web nginx=nginx:1.15
# 查看升级状态
[root@k8smaster ~]# kubectl rollout status deploy web
deployment "web" successfully rolled out
# 查看版本历史
[root@k8smaster ~]# kubectl rollout history deploy web
deployment.apps/web
REVISION  CHANGE-CAUSE
1         <none>
2         <none>
# 回滚到上一个版本
[root@k8smaster ~]# kubectl rollout undo deploy web
deployment.apps/web rolled back
# 回滚到指定版本
[root@k8smaster ~]# kubectl rollout undo deploy web --to-revision=2
deployment.apps/web rolled back

二动态扩缩容

# 当前pod副本
[root@k8smaster ~]# kubectl get pods
NAME                  READY   STATUS    RESTARTS   AGE
web-bbcf684cb-7g6mk   1/1     Running   0          51s
web-bbcf684cb-rsdv4   1/1     Running   0          65s
# 扩展副本10
[root@k8smaster ~]# kubectl scale deploy web --replicas=10
deployment.apps/web scaled
# 查看
[root@k8smaster ~]# kubectl get pods
NAME                  READY   STATUS              RESTARTS   AGE
web-bbcf684cb-29fkb   1/1     Running             0          36s
web-bbcf684cb-6kj7n   1/1     Running             0          36s
web-bbcf684cb-7g6mk   1/1     Running             0          2m4s
web-bbcf684cb-bt7xd   0/1     ContainerCreating   0          36s
web-bbcf684cb-d9b2v   0/1     ContainerCreating   0          35s
web-bbcf684cb-hjx5c   0/1     ContainerCreating   0          36s
web-bbcf684cb-hlkqw   0/1     ContainerCreating   0          35s
web-bbcf684cb-rsdv4   1/1     Running             0          2m18s
web-bbcf684cb-tj4f9   0/1     ContainerCreating   0          35s
web-bbcf684cb-wcrzq   0/1     ContainerCreating   0          36s