关于kubernetes:kubernetes核心实战四-Deployments

6、Deployments（重点）

一个 Deployment 控制器为 Pods和 ReplicaSets提供描述性的更新形式。

形容 Deployment 中的 desired state，并且 Deployment 控制器以受控速率更改理论状态，以达到冀望状态。能够定义 Deployments 以创立新的 ReplicaSets ，或删除现有 Deployments ，并通过新的 Deployments 应用其所有资源。

用例

以下是典型的 Deployments 用例：

创立 Deployment 以开展 ReplicaSet 。ReplicaSet 在后盾创立 Pods。查看 ReplicaSet 开展的状态，查看其是否胜利。

申明 Pod 的新状态通过更新 Deployment 的 PodTemplateSpec。将创立新的 ReplicaSet ，并且 Deployment 管理器以受控速率将 Pod 从旧 ReplicaSet 挪动到新 ReplicaSet 。每个新的 ReplicaSet 都会更新 Deployment 的批改历史。

回滚到较早的 Deployment 版本，如果 Deployment 的以后状态不稳固。每次回滚都会更新 Deployment 的批改。

扩大 Deployment 以承当更多负载.

暂停 Deployment 对其 PodTemplateSpec 进行批改，而后复原它以启动新的开展。

应用 Deployment 状态作为卡住开展的指示器。

清理较旧的 ReplicaSets ，那些不再须要的。

1）创立 Deployment

[root@k8s-master-node1 ~/yaml/test]# vim deployments.yaml[root@k8s-master-node1 ~/yaml/test]# cat deployments.yaml apiVersion: apps/v1kind: Deploymentmetadata:  name: nginx-deployment  labels:    app: nginxspec:  replicas: 3  selector:    matchLabels:      app: nginx  template:    metadata:      labels:        app: nginx    spec:      containers:      - name: nginx        image: nginx:1.14.2        ports:        - containerPort: 80[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]# kubectl apply -f deployments.yaml deployment.apps/nginx-deployment created[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]#

含意介绍：

在该例中：将创立名为 nginx-deployment 的 Deployment ，由 .metadata.name 字段批示。

Deployment 创立三个复制的 Pods，由 replicas 字段批示。

selector 字段定义 Deployment 如何查找要治理的 Pods。在这种状况下，只需抉择在 Pod 模板（app: nginx）中定义的标签。然而，更简单的抉择规定是可能的，只有 Pod 模板自身满足规定。

阐明：

matchLabels 字段是 {key,value} 的映射。单个 {key,value}在 matchLabels 映射中的值等效于 matchExpressions 的元素，其键字段是“key”，运算符为“In”，值数组仅蕴含“value”。所有要求，从 matchLabels 和 matchExpressions，必须满足能力匹配。

template 字段蕴含以下子字段：

Pod 标记为app: nginx，应用labels字段。

Pod 模板标准或 .template.spec 字段批示 Pods 运行一个容器， nginx，运行 nginx Docker Hub版本1.7.9的镜像。

创立一个容器并应用name字段将其命名为 nginx。

查看具体的字段解释：

[root@k8s-master-node1 ~]# kubectl  explain Deployment.specKIND:     DeploymentVERSION:  apps/v1RESOURCE: spec <Object>DESCRIPTION:     Specification of the desired behavior of the Deployment.     DeploymentSpec is the specification of the desired behavior of the     Deployment.FIELDS:   minReadySeconds<integer>     Minimum number of seconds for which a newly created pod should be ready     without any of its container crashing, for it to be considered available.     Defaults to 0 (pod will be considered available as soon as it is ready)   paused<boolean>     Indicates that the deployment is paused.   progressDeadlineSeconds<integer>     The maximum time in seconds for a deployment to make progress before it is     considered to be failed. The deployment controller will continue to process     failed deployments and a condition with a ProgressDeadlineExceeded reason     will be surfaced in the deployment status. Note that progress will not be     estimated during the time a deployment is paused. Defaults to 600s.   replicas<integer>     Number of desired pods. This is a pointer to distinguish between explicit     zero and not specified. Defaults to 1.   revisionHistoryLimit<integer>     The number of old ReplicaSets to retain to allow rollback. This is a     pointer to distinguish between explicit zero and not specified. Defaults to     10.   selector <Object> -required-     Label selector for pods. Existing ReplicaSets whose pods are selected by     this will be the ones affected by this deployment. It must match the pod     template's labels.   strategy<Object>     The deployment strategy to use to replace existing pods with new ones.   template <Object> -required-     Template describes the pods that will be created.[root@k8s-master-node1 ~]#

查看pod

[root@k8s-master-node1 ~/yaml/test]# kubectl get pod NAME                                     READY   STATUS        RESTARTS     AGEingress-demo-app-694bf5d965-q4l7m        1/1     Terminating   0            23hingress-demo-app-694bf5d965-v28sl        1/1     Running       0            3m9singress-demo-app-694bf5d965-v652j        1/1     Running       0            23hnfs-client-provisioner-dc5789f74-nnk77   1/1     Running       1 (8h ago)   22hnginx-deployment-66b6c48dd5-5hhjq        1/1     Running       0            3m9snginx-deployment-66b6c48dd5-9z2n5        1/1     Running       0            3m19snginx-deployment-66b6c48dd5-llq7c        1/1     Running       0            9m10s[root@k8s-master-node1 ~/yaml/test]#

查看deployments

[root@k8s-master-node1 ~/yaml/test]# kubectl get deployments.apps NAME                     READY   UP-TO-DATE   AVAILABLE   AGEingress-demo-app         2/2     2            2           23hnfs-client-provisioner   1/1     1            1           22hnginx-deployment         3/3     3            3           9m45s[root@k8s-master-node1 ~/yaml/test]#

解释阐明：

查看集群中的 Deployments 时，将显示以下字段：

NAME 列出了集群中 Deployments 的名称。

DESIRED 显示应用程序的所需正本数，在创立 Deployment 时定义这些正本。这是冀望状态。

CURRENT显示以后正在运行的正本数。

UP-TO-DATE显示已更新以实现冀望状态的正本数。

AVAILABLE显示应用程序可供用户应用的正本数。

AGE 显示利用程序运行的工夫量。

查看rs

[root@k8s-master-node1 ~/yaml/test]# kubectl get replicasets.apps NAME                               DESIRED   CURRENT   READY   AGEingress-demo-app-694bf5d965        2         2         2       23hnfs-client-provisioner-dc5789f74   1         1         1       23hnginx-deployment-66b6c48dd5        3         3         3       19m[root@k8s-master-node1 ~/yaml/test]#

查看pods的标签

[root@k8s-master-node1 ~/yaml/test]# kubectl get pods --show-labelsNAME                                     READY   STATUS        RESTARTS     AGE   LABELSingress-demo-app-694bf5d965-q4l7m        1/1     Terminating   0            23h   app=ingress-demo-app,pod-template-hash=694bf5d965ingress-demo-app-694bf5d965-v28sl        1/1     Running       0            15m   app=ingress-demo-app,pod-template-hash=694bf5d965ingress-demo-app-694bf5d965-v652j        1/1     Running       0            23h   app=ingress-demo-app,pod-template-hash=694bf5d965nfs-client-provisioner-dc5789f74-nnk77   1/1     Running       1 (8h ago)   23h   app=nfs-client-provisioner,pod-template-hash=dc5789f74nginx-deployment-66b6c48dd5-48k9j        0/1     Terminating   0            21m   app=nginx,pod-template-hash=66b6c48dd5nginx-deployment-66b6c48dd5-5hhjq        1/1     Running       0            15m   app=nginx,pod-template-hash=66b6c48dd5nginx-deployment-66b6c48dd5-9z2n5        1/1     Running       0            15m   app=nginx,pod-template-hash=66b6c48dd5nginx-deployment-66b6c48dd5-kvzft        0/1     Terminating   0            21m   app=nginx,pod-template-hash=66b6c48dd5nginx-deployment-66b6c48dd5-llq7c        1/1     Running       0            21m   app=nginx,pod-template-hash=66b6c48dd5[root@k8s-master-node1 ~/yaml/test]#

2）更新回滚 Deployment

命令行行降级应用镜像

[root@k8s-master-node1 ~/yaml/test]# kubectl get deployments -o wideNAME                     READY   UP-TO-DATE   AVAILABLE   AGE   CONTAINERS               IMAGES                                                                                    SELECTORingress-demo-app         2/2     2            2           23h   whoami                   traefik/whoami:v1.6.1                                                                     app=ingress-demo-appnfs-client-provisioner   1/1     1            1           23h   nfs-client-provisioner   registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images/nfs-subdir-external-provisioner:v4.0.2   app=nfs-client-provisionernginx-deployment         3/3     3            3           18m   nginx                    nginx:1.14.2                                                                              app=nginx[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]# kubectl --record deployment.apps/nginx-deployment set image deployment.v1.apps/nginx-deployment nginx=nginx:1.20.1Flag --record has been deprecated, --record will be removed in the futuredeployment.apps/nginx-deployment image updateddeployment.apps/nginx-deployment image updated[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]# kubectl get deployments -o wideNAME                     READY   UP-TO-DATE   AVAILABLE   AGE   CONTAINERS               IMAGES                                                                                    SELECTORingress-demo-app         2/2     2            2           23h   whoami                   traefik/whoami:v1.6.1                                                                     app=ingress-demo-appnfs-client-provisioner   1/1     1            1           23h   nfs-client-provisioner   registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images/nfs-subdir-external-provisioner:v4.0.2   app=nfs-client-provisionernginx-deployment         3/3     1            3           24m   nginx                    nginx:1.20.1                                                                              app=nginx[root@k8s-master-node1 ~/yaml/test]#

yaml形式批改镜像

[root@k8s-master-node1 ~/yaml/test]# kubectl edit deployments.apps nginx-deploymentEdit cancelled, no changes made.[root@k8s-master-node1 ~/yaml/test]#

查看更新过程

[root@k8s-master-node1 ~/yaml/test]# kubectl rollout status deployment.v1.apps/nginx-deploymentWaiting for deployment "nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...deployment "nginx-deployment" successfully rolled out[root@k8s-master-node1 ~/yaml/test]#

查看详细信息

[root@k8s-master-node1 ~/yaml/test]# kubectl describe deploymentsName:                   ingress-demo-appNamespace:              defaultCreationTimestamp:      Tue, 16 Nov 2021 13:28:26 +0800Labels:                 app=ingress-demo-appAnnotations:            deployment.kubernetes.io/revision: 1Selector:               app=ingress-demo-appReplicas:               2 desired | 2 updated | 2 total | 2 available | 0 unavailableStrategyType:           RollingUpdateMinReadySeconds:        0RollingUpdateStrategy:  25% max unavailable, 25% max surgePod Template:  Labels:  app=ingress-demo-app  Containers:   whoami:    Image:        traefik/whoami:v1.6.1    Port:         80/TCP    Host Port:    0/TCP    Environment:  <none>    Mounts:       <none>  Volumes:        <none>Conditions:  Type           Status  Reason  ----           ------  ------  Progressing    True    NewReplicaSetAvailable  Available      True    MinimumReplicasAvailableOldReplicaSets:  <none>NewReplicaSet:   ingress-demo-app-694bf5d965 (2/2 replicas created)Events:  Type    Reason             Age   From                   Message  ----    ------             ----  ----                   -------  Normal  ScalingReplicaSet  23h   deployment-controller  Scaled up replica set ingress-demo-app-694bf5d965 to 2Name:               nfs-client-provisionerNamespace:          defaultCreationTimestamp:  Tue, 16 Nov 2021 14:07:33 +0800Labels:             app=nfs-client-provisionerAnnotations:        deployment.kubernetes.io/revision: 1Selector:           app=nfs-client-provisionerReplicas:           1 desired | 1 updated | 1 total | 1 available | 0 unavailableStrategyType:       RecreateMinReadySeconds:    0Pod Template:  Labels:           app=nfs-client-provisioner  Service Account:  nfs-client-provisioner  Containers:   nfs-client-provisioner:    Image:      registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images/nfs-subdir-external-provisioner:v4.0.2    Port:       <none>    Host Port:  <none>    Environment:      PROVISIONER_NAME:  k8s-sigs.io/nfs-subdir-external-provisioner      NFS_SERVER:        192.168.1.66      NFS_PATH:          /nfs/    Mounts:      /persistentvolumes from nfs-client-root (rw)  Volumes:   nfs-client-root:    Type:      NFS (an NFS mount that lasts the lifetime of a pod)    Server:    192.168.1.66    Path:      /nfs/    ReadOnly:  falseConditions:  Type           Status  Reason  ----           ------  ------  Progressing    True    NewReplicaSetAvailable  Available      True    MinimumReplicasAvailableOldReplicaSets:  <none>NewReplicaSet:   nfs-client-provisioner-dc5789f74 (1/1 replicas created)Events:  Type    Reason             Age   From                   Message  ----    ------             ----  ----                   -------  Normal  ScalingReplicaSet  23h   deployment-controller  Scaled up replica set nfs-client-provisioner-dc5789f74 to 1Name:                   nginx-deploymentNamespace:              defaultCreationTimestamp:      Wed, 17 Nov 2021 12:54:46 +0800Labels:                 app=nginxAnnotations:            deployment.kubernetes.io/revision: 3                        kubernetes.io/change-cause:                          kubectl deployment.apps/nginx-deployment set image deployment.v1.apps/nginx-deployment nginx=nginx:1.20.1 --record=trueSelector:               app=nginxReplicas:               3 desired | 3 updated | 3 total | 3 available | 0 unavailableStrategyType:           RollingUpdateMinReadySeconds:        0RollingUpdateStrategy:  25% max unavailable, 25% max surgePod Template:  Labels:  app=nginx  Containers:   nginx:    Image:        nginx:1.16.1    Port:         80/TCP    Host Port:    0/TCP    Environment:  <none>    Mounts:       <none>  Volumes:        <none>Conditions:  Type           Status  Reason  ----           ------  ------  Available      True    MinimumReplicasAvailable  Progressing    True    NewReplicaSetAvailableOldReplicaSets:  <none>NewReplicaSet:   nginx-deployment-559d658b74 (3/3 replicas created)Events:  Type    Reason             Age                From                   Message  ----    ------             ----               ----                   -------  Normal  ScalingReplicaSet  30m                deployment-controller  Scaled up replica set nginx-deployment-66b6c48dd5 to 3  Normal  ScalingReplicaSet  5m55s              deployment-controller  Scaled up replica set nginx-deployment-58b9b8ff79 to 1  Normal  ScalingReplicaSet  5m27s              deployment-controller  Scaled down replica set nginx-deployment-66b6c48dd5 to 2  Normal  ScalingReplicaSet  5m27s              deployment-controller  Scaled up replica set nginx-deployment-58b9b8ff79 to 2  Normal  ScalingReplicaSet  5m                 deployment-controller  Scaled down replica set nginx-deployment-66b6c48dd5 to 1  Normal  ScalingReplicaSet  5m                 deployment-controller  Scaled up replica set nginx-deployment-58b9b8ff79 to 3  Normal  ScalingReplicaSet  4m56s              deployment-controller  Scaled down replica set nginx-deployment-66b6c48dd5 to 0  Normal  ScalingReplicaSet  78s                deployment-controller  Scaled up replica set nginx-deployment-559d658b74 to 1  Normal  ScalingReplicaSet  63s                deployment-controller  Scaled down replica set nginx-deployment-58b9b8ff79 to 2  Normal  ScalingReplicaSet  63s                deployment-controller  Scaled up replica set nginx-deployment-559d658b74 to 2  Normal  ScalingReplicaSet  49s (x3 over 61s)  deployment-controller  (combined from similar events): Scaled down replica set nginx-deployment-58b9b8ff79 to 0[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]#

3） Deployment历史记录

查看历史

[root@k8s-master-node1 ~/yaml/test]# kubectl rollout history deployment.v1.apps/nginx-deploymentdeployment.apps/nginx-deployment REVISION  CHANGE-CAUSE1         <none>2         kubectl deployment.apps/nginx-deployment set image deployment.v1.apps/nginx-deployment nginx=nginx:1.20.1 --record=true3         kubectl deployment.apps/nginx-deployment set image deployment.v1.apps/nginx-deployment nginx=nginx:1.20.1 --record=true[root@k8s-master-node1 ~/yaml/test]#

回滚到上次

[root@k8s-master-node1 ~/yaml/test]# kubectl rollout undo deployment.v1.apps/nginx-deploymentdeployment.apps/nginx-deployment rolled back[root@k8s-master-node1 ~/yaml/test]# kubectl rollout status deployment.v1.apps/nginx-deploymentWaiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...deployment "nginx-deployment" successfully rolled out[root@k8s-master-node1 ~/yaml/test]#

回滚到指定版本

[root@k8s-master-node1 ~/yaml/test]# kubectl rollout undo deployment.v1.apps/nginx-deployment --to-revision=3deployment.apps/nginx-deployment rolled back[root@k8s-master-node1 ~/yaml/test]# kubectl rollout status deployment.v1.apps/nginx-deploymentWaiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...deployment "nginx-deployment" successfully rolled out[root@k8s-master-node1 ~/yaml/test]#

4）缩放 Deployment

扩容到十个pod

[root@k8s-master-node1 ~/yaml/test]# kubectl scale deployment.v1.apps/nginx-deployment --replicas=10deployment.apps/nginx-deployment scaled[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]# kubectl  get deployments.appsNAME                     READY   UP-TO-DATE   AVAILABLE   AGEingress-demo-app         0/2     2            0           24hnfs-client-provisioner   0/1     1            0           23hnginx-deployment         5/10    10           5           45m[root@k8s-master-node1 ~/yaml/test]#

假如启用程度主动缩放 Pod在集群中，能够为 Deployment 设置主动缩放器，并抉择最小和最大要基于现有 Pods 的 CPU 利用率运行的 Pods。

[root@k8s-master-node1 ~/yaml/test]# kubectl autoscale deployment.v1.apps/nginx-deployment --min=10 --max=15 --cpu-percent=80horizontalpodautoscaler.autoscaling/nginx-deployment autoscaled[root@k8s-master-node1 ~/yaml/test]# [root@k8s-master-node1 ~/yaml/test]#

https://blog.csdn.net/qq\_33921750

https://my.oschina.net/u/3981543

https://www.zhihu.com/people/...

https://segmentfault.com/u/hp...

https://juejin.cn/user/331578...

https://space.bilibili.com/35...

https://cloud.tencent.com/dev...

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本文应用文章同步助手同步#### 6、Deployments（重点）