一、Deployment 定义

  1、简介

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[root@k8smaster manifests]# kubectl explain deploy(也可以写作deployment)
KIND:     Deployment
VERSION:  extensions/v1beta1 #属于该群组,但是1.10包括1.11版本中其已经被摞到另外一个群组 apps/v1 版中,因此这个文档的版本是落后于我们k8s自身的。

DESCRIPTION:
     DEPRECATED - This group version of Deployment is deprecated by
     apps/v1beta2/Deployment. #此版本也是老版的,当前1.11版本为apps/v1  See the release notes for more information.
     Deployment enables declarative updates for Pods and ReplicaSets.

FIELDS:
   apiVersion    <string>
     APIVersion defines the versioned schema of this representation of an
     object. Servers should convert recognized schemas to the latest internal
     value, and may reject unrecognized values. More info:
     https://git.k8s.io/community/contributors/devel/api-conventions.md#resources

   kind    <string>
     Kind is a string value representing the REST resource this object
     represents. Servers may infer this from the endpoint the client submits
     requests to. Cannot be updated. In CamelCase. More info:
     https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kinds

   metadata    <Object>
     Standard object metadata.

   spec    <Object>
     Specification of the desired behavior of the Deployment.

   status    <Object>
     Most recently observed status of the Deployment.

    deployment.spec 简介

[root@k8smaster manifests]# kubectl explain deployment.spec
KIND:     Deployment
VERSION:  extensions/v1beta1

RESOURCE: 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> #暂停,默认都是不暂停的上来就更新
     Indicates that the deployment is paused and will not be processed by the
     deployment controller.

   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. This is not set by
     default.

   replicas    <integer>
     Number of desired pods. This is a pointer to distinguish between explicit
     zero and not specified. Defaults to 1.

   revisionHistoryLimit    <integer> #我们在滚动更新中最多在历史中保存过去多少个历史版本,默认为10个
     The number of old ReplicaSets to retain to allow rollback. This is a
     pointer to distinguish between explicit zero and not specified.

   rollbackTo    <Object>
     DEPRECATED. The config this deployment is rolling back to. Will be cleared
     after rollback is done.

   selector    <Object>
     Label selector for pods. Existing ReplicaSets whose pods are selected by
     this will be the ones affected by this deployment.

   strategy    <Object> #更新策略
     The deployment strategy to use to replace existing pods with new ones.

   template    <Object> -required-
     Template describes the pods that will be created.

    deployment.spec.strategy #更新策略

[root@k8smaster manifests]# kubectl explain deployment.spec.strategy
KIND:     Deployment
VERSION:  extensions/v1beta1

RESOURCE: strategy <Object>

DESCRIPTION:
     The deployment strategy to use to replace existing pods with new ones.

     DeploymentStrategy describes how to replace existing pods with new ones.

FIELDS:
   rollingUpdate    <Object> #滚动更新
     Rolling update config params. Present only if DeploymentStrategyType =
     RollingUpdate.

   type    <string>
     Type of deployment. Can be "Recreate" or "RollingUpdate". Default is
     RollingUpdate. #重建式更新Recreate,还有滚动更新RollingUpdate,若使用RollingUpdate,还可以控制更新粒度
  

    deployment.spec.strategy.rollingUpdate  #更新粒度

[root@k8smaster manifests]# kubectl explain deployment.spec.strategy.rollingUpdate
KIND:     Deployment
VERSION:  extensions/v1beta1

RESOURCE: rollingUpdate <Object>

DESCRIPTION:
     Rolling update config params. Present only if DeploymentStrategyType =
     RollingUpdate.

     Spec to control the desired behavior of rolling update.

FIELDS:
   maxSurge    <string> #对应的更新过程中最多能超出所指定的目标副本数有几个,有两种取值方式,第一直接指定数量,第二百分比。     
The maximum number of pods that can be scheduled above the desired number of pods. Value can be an absolute number (ex:
5) or a percentage of desired pods (ex: 10%). This can not be 0 if MaxUnavailable is 0. Absolute number is calculated from percentage by rounding up. By default, a value of 1 is used. Example: when this is set to 30%, the new RC can be scaled up immediately when the rolling update starts, such that the total number of old and new pods do not exceed 130% of desired pods. Once old pods have been killed, new RC can be scaled up further, ensuring that total number of pods running at any time during the update is atmost 130% of desired pods. maxUnavailable <string>#表示最多有几个不可用,和上述一样也是两种取值方式 The maximum number of pods that can be unavailable during the update. Value can be an absolute number (ex: 5) or a percentage of desired pods (ex: 10%). Absolute number is calculated from percentage by rounding down. This can not be 0 if MaxSurge is 0. By default, a fixed value of 1 is used. Example: when this is set to 30%, the old RC can be scaled down to 70% of desired pods immediately when the rolling update starts. Once new pods are ready, old RC can be scaled down further, followed by scaling up the new RC, ensuring that the total number of pods available at all times during the update is at least 70% of desired pods.

  2、deployment具体操作

[root@k8smaster manifests]# cat deploy-demo.yaml 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
  namespace: default
spec:
  replicas: 2
  selector: 
    matchLabels:
      app: myapp
      release: canary
  template:
    metadata:
      labels:
        app: myapp
        release: canary
    spec:
      containers:
      - name: myapp
        image: ikubernetes/myapp:v1
        ports: 
        - name: http
          containerPort: 80 


[root@k8smaster manifests]# kubectl get deployment -o wide
NAME           DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE       CONTAINERS   IMAGES                 SELECTOR
myapp-deploy   2         2         2            2           1m        myapp        ikubernetes/myapp:v1   app=myapp,release=canary
[root@k8smaster manifests]# kubectl get rs -o wide #会发现自动创建了rs
NAME                      DESIRED   CURRENT   READY     AGE       CONTAINERS   IMAGES                 SELECTOR
myapp-deploy-69b47bc96d #后面的数值为模板的哈希值   2         2         2         1m        myapp        ikubernetes/myapp:v1   app=myapp,pod-template-hash=2560367528,release=canary

[root@k8smaster manifests]# kubectl get pods -o wide --show-labels
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
liveness-httpget-pod            1/1       Running   1          1d        10.244.2.18   k8snode2   <none>
myapp-deploy-69b47bc96d-47b9t #会发现pod命名由rs + 后面一串随机字符组成  1/1       Running   0          5m        10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   1/1       Running   0          5m        10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
poststart-pod                   1/1       Running   8          1d        10.244.2.21   k8snode2   <none>
readiness-httpget-pod           1/1       Running   0          1d        10.244.2.19   k8snode2   <none>

    a、在更新应用时可以直接通过编辑配置文件来实现,编辑后再次执行apply -f  deploy-demo.yaml即可,但是create就不行了。其原理为每一次变化其将同步至api server中,api server发现与etcd中的状态不同从而改变etcd从而实现修改他的期望状态。从而将现有状态不断逼近期望状态。

[root@k8smaster manifests]# kubectl get pods -o wide --show-labels
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
liveness-httpget-pod            1/1       Running   1          1d        10.244.2.18   k8snode2   <none>
myapp-deploy-69b47bc96d-47b9t   1/1       Running   0          5m        10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   1/1       Running   0          5m        10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
poststart-pod                   1/1       Running   8          1d        10.244.2.21   k8snode2   <none>
readiness-httpget-pod           1/1       Running   0          1d        10.244.2.19   k8snode2   <none>
[root@k8smaster manifests]# sed -i 's/replicas: 2/replicas: 3/g' deploy-demo.yaml 
[root@k8smaster manifests]# kubectl apply -f deploy-demo.yaml 
deployment.apps/myapp-deploy configured
[root@k8smaster manifests]# kubectl get pods -o wide --show-labels
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
liveness-httpget-pod            1/1       Running   1          1d        10.244.2.18   k8snode2   <none>
myapp-deploy-69b47bc96d-47b9t   1/1       Running   0          15m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-75jgw   1/1       Running   0          16s       10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   1/1       Running   0          15m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
poststart-pod                   1/1       Running   8          1d        10.244.2.21   k8snode2   <none>
readiness-httpget-pod           1/1       Running   0          1d        10.244.2.19   k8snode2   <none>
[root@k8smaster manifests]# kubectl describe deploy myapp-deploy
Name:                   myapp-deploy
Namespace:              default
CreationTimestamp:      Thu, 16 May 2019 14:14:58 +0800
Labels:                 <none>
Annotations(注释):            deployment.kubernetes.io/revision=1 #我们每一次apply版本发生变化时的信息都会被保存在其中。
                        kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"apps/v1","kind":"Deployment","metadata":{"annotations":{},"name":"myapp-deploy","namespace":"default"
},"spec":{"replicas":3,"selector":{...Selector:               app=myapp,release=canary
Replicas:               3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType:           RollingUpdate #默认的更新策略为滚动更新
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge #滚动更新的中心策略是最多不可用25%,最多多出25%
Pod Template:
  Labels:  app=myapp
           release=canary
  Containers:
   myapp:
    Image:        ikubernetes/myapp:v1
    Port:         80/TCP
    Host Port:    0/TCP
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Progressing    True    NewReplicaSetAvailable
  Available      True    MinimumReplicasAvailable
OldReplicaSets:  <none>
NewReplicaSet:   myapp-deploy-69b47bc96d (3/3 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  18m   deployment-controller  Scaled up replica set myapp-deploy-69b47bc96d to 2
  Normal  ScalingReplicaSet  2m    deployment-controller  Scaled up replica set myapp-deploy-69b47bc96d to 3

  3、滚动更新

    a、直接修改yaml文件后再执行 kubectl apply -f deploy-demo.yaml

[root@k8smaster manifests]# sed -i 's#image: ikubernetes/myapp:v1#image: ikubernetes/myapp:v2#g' deploy-demo.yaml 

[root@k8smaster manifests]# kubectl apply -f deploy-demo.yaml 
deployment.apps/myapp-deploy configured

#另起一个窗口动态监测更新过程
[root@k8smaster manifests]# kubectl get pods -o wide --show-labels -l app=myapp -w
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
myapp-deploy-69b47bc96d-47b9t   1/1       Running   0          24m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-75jgw   1/1       Running   0          8m        10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   1/1       Running   0          24m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-67f6f6b4dc-6hbjh   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-6hbjh   0/1       Pending   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-6hbjh   0/1       ContainerCreating   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-6hbjh   1/1       Running   0         1s        10.244.1.31   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d-75jgw   1/1       Terminating   0         14m       10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   0/1       Pending   0         0s        <none>    k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   0/1       ContainerCreating   0         0s        <none>    k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d-75jgw   0/1       Terminating   0         14m       10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   1/1       Running   0         2s        10.244.2.25   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d-47b9t   1/1       Terminating   0         30m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   0/1       Pending   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   0/1       ContainerCreating   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d-75jgw   0/1       Terminating   0         14m       10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-75jgw   0/1       Terminating   0         14m       10.244.1.30   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   1/1       Running   0         1s        10.244.1.32   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d-47b9t   0/1       Terminating   0         30m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   1/1       Terminating   0         30m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   0/1       Terminating   0         30m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-47b9t   0/1       Terminating   0         30m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-47b9t   0/1       Terminating   0         30m       10.244.1.29   k8snode1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   0/1       Terminating   0         30m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-69b47bc96d-bnqk9   0/1       Terminating   0         30m       10.244.2.24   k8snode2   app=myapp,pod-template-hash=2560367528,release=canary


[root@k8smaster manifests]# kubectl get rs -o wide #发现老版本rs依然存在,只是运行的pod为0
NAME                      DESIRED   CURRENT   READY     AGE       CONTAINERS   IMAGES                 SELECTOR
myapp-deploy-67f6f6b4dc   3         3         3         2m        myapp        ikubernetes/myapp:v2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d   0         0         0         33m       myapp        ikubernetes/myapp:v1   app=myapp,pod-template-hash=2560367528,release=canary

#查看deployment的滚动历史
[root@k8smaster manifests]# kubectl rollout history deployment myapp-deploy
deployments "myapp-deploy"
REVISION  CHANGE-CAUSE
1         <none>
2         <none>

    b、通过patch命令,其补的一定是对象的json格式的内容

[root@k8smaster manifests]# kubectl patch deployment myapp-deploy -p '{"spec":{"replicas":5}}'
deployment.extensions/myapp-deploy patched
[root@k8smaster manifests]# kubectl get pods -o wide --show-labels
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
liveness-httpget-pod            1/1       Running   1          1d        10.244.2.18   k8snode2   <none>
myapp-deploy-67f6f6b4dc-6hbjh   1/1       Running   0          14m       10.244.1.31   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   1/1       Running   0          36s       10.244.1.33   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   1/1       Running   0          14m       10.244.2.25   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   1/1       Running   0          14m       10.244.1.32   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   1/1       Running   0          36s       10.244.2.26   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
poststart-pod                   1/1       Running   9          1d        10.244.2.21   k8snode2   <none>
readiness-httpget-pod           1/1       Running   0          1d        10.244.2.19   k8snode2   <none>

#另起一个shell查看更新过程
[root@k8smaster manifests]# kubectl get pods -o wide --show-labels -l app=myapp -w
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
myapp-deploy-67f6f6b4dc-6hbjh   1/1       Running   0          11m       10.244.1.31   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   1/1       Running   0          11m       10.244.2.25   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   1/1       Running   0          11m       10.244.1.32   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   0/1       Pending   0         0s        <none>    k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   0/1       Pending   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   0/1       ContainerCreating   0         0s        <none>    k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   0/1       ContainerCreating   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   1/1       Running   0         2s        10.244.2.26   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   1/1       Running   0         2s        10.244.1.33   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary

    c、设置更新过程中最多超出1个,最多0个不可用

[root@k8smaster manifests]# kubectl patch deployment myapp-deploy -p '{"spec":{"strategy":{"rollingUpdate":{"maxSurge":1,"maxUnavailable":0}}}}'
deployment.extensions/myapp-deploy patched
[root@k8smaster manifests]# kubectl edit deployment myapp-deploy #可以进入看到更新后的属性
Edit cancelled, no changes made.
[root@k8smaster manifests]# kubectl describe deployment myapp-deploy
Name:                   myapp-deploy
Namespace:              default
CreationTimestamp:      Thu, 16 May 2019 14:14:58 +0800
Labels:                 app=myapp
                        release=canary
Annotations:            deployment.kubernetes.io/revision=2
                        kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"apps/v1","kind":"Deployment","metadata":{"annotations":{},"name":"myapp-deploy","namespace":"default"
},"spec":{"replicas":3,"selector":{...Selector:               app=myapp,release=canary
Replicas:               5 desired | 5 updated | 5 total | 5 available | 0 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  0 max unavailable, 1 max surge
Pod Template:
  Labels:  app=myapp
           release=canary
  Containers:
   myapp:
    Image:        ikubernetes/myapp:v2
    Port:         80/TCP
    Host Port:    0/TCP
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Progressing    True    NewReplicaSetAvailable
  Available      True    MinimumReplicasAvailable
OldReplicaSets:  <none>
NewReplicaSet:   myapp-deploy-67f6f6b4dc (5/5 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  56m   deployment-controller  Scaled up replica set myapp-deploy-69b47bc96d to 2
  Normal  ScalingReplicaSet  40m   deployment-controller  Scaled up replica set myapp-deploy-69b47bc96d to 3
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled up replica set myapp-deploy-67f6f6b4dc to 1
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled down replica set myapp-deploy-69b47bc96d to 2
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled up replica set myapp-deploy-67f6f6b4dc to 2
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled down replica set myapp-deploy-69b47bc96d to 1
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled up replica set myapp-deploy-67f6f6b4dc to 3
  Normal  ScalingReplicaSet  26m   deployment-controller  Scaled down replica set myapp-deploy-69b47bc96d to 0
  Normal  ScalingReplicaSet  12m   deployment-controller  Scaled up replica set myapp-deploy-67f6f6b4dc to 5

    d、通过使用set image命令

[root@k8smaster manifests]# kubectl set image deployment myapp-deploy myapp=ikubernetes/myapp:v3 && kubectl rollout pause  #设置后立马暂停deployment myapp-deploy,这样就只会更新一个镜像为v3的pod。(金丝雀发布)
deployment.extensions/myapp-deploy image updated
deployment.extensions/myapp-deploy paused

#另起一个窗口观察
[root@k8smaster manifests]# kubectl get pods -o wide --show-labels -l app=myapp -w
NAME                            READY     STATUS    RESTARTS   AGE       IP            NODE       LABELS
myapp-deploy-67f6f6b4dc-6hbjh   1/1       Running   0          23m       10.244.1.31   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-9hhb4   1/1       Running   0          9m        10.244.1.33   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-bqtpz   1/1       Running   0          23m       10.244.2.25   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-xb6qw   1/1       Running   0          23m       10.244.1.32   k8snode1   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-67f6f6b4dc-z54x6   1/1       Running   0          9m        10.244.2.26   k8snode2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       Pending   0         0s        <none>    <none>    app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       Pending   0         0s        <none>    k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       ContainerCreating   0         1s        <none>    k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       ErrImagePull   0         2s        10.244.1.34   k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       ImagePullBackOff   0         3s        10.244.1.34   k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       ErrImagePull   0         29s       10.244.1.34   k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   0/1       ImagePullBackOff   0         39s       10.244.1.34   k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
myapp-deploy-6bdcd6755d-n4qbt   1/1       Running   0         46s       10.244.1.34   k8snode1   app=myapp,pod-template-hash=2687823118,release=canary
[root@k8smaster manifests]# kubectl rollout status deployment myapp-deploy  #监视更新变化目前显示一个被更新
Waiting for deployment "myapp-deploy" rollout to finish: 1 out of 5 new replicas have been updated...

#当确定新版本使用没问题时,解除暂停更新的操作继续更新
[root@k8smaster ~]# kubectl rollout resume deployment myapp-deploy
deployment.extensions/myapp-deploy resumed

#另一个窗口查看更新情况
[root@k8smaster manifests]# kubectl rollout status deployment myapp-deploy 
Waiting for deployment "myapp-deploy" rollout to finish: 1 out of 5 new replicas have been updated...
Waiting for deployment spec update to be observed...
Waiting for deployment spec update to be observed...
Waiting for deployment "myapp-deploy" rollout to finish: 1 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 1 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 2 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 2 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 4 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 4 out of 5 new replicas have been updated...
Waiting for deployment "myapp-deploy" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "myapp-deploy" rollout to finish: 1 old replicas are pending termination...
deployment "myapp-deploy" successfully rolled out
[root@k8smaster manifests]# kubectl get rs -o wide #此时查看rs版本
NAME                      DESIRED   CURRENT   READY     AGE       CONTAINERS   IMAGES                 SELECTOR
myapp-deploy-67f6f6b4dc   0         0         0         51m       myapp        ikubernetes/myapp:v2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d   0         0         0         1h        myapp        ikubernetes/myapp:v1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-6bdcd6755d   5         5         5         17m       myapp        ikubernetes/myapp:v3   app=myapp,pod-template-hash=2687823118,release=canary

[root@k8smaster manifests]# kubectl rollout history deployment myapp-deploy #查看历史更新版本
deployments "myapp-deploy"
REVISION  CHANGE-CAUSE
1         <none>
2         <none>
3         <none>

  4、回滚

[root@k8smaster ~]# kubectl rollout history deployment myapp-deploy #查看当前版本
deployments "myapp-deploy"
REVISION  CHANGE-CAUSE
1         <none>
2         <none>
3         <none>

[root@k8smaster ~]# kubectl rollout undo deployment myapp-deploy --to-revision=1 #回滚到版本1
deployment.extensions/myapp-deploy
[root@k8smaster ~]# kubectl rollout history deployment myapp-deploy #查看回滚后的版本,当前版本变为了4,前一个为版本3
deployments "myapp-deploy"
REVISION  CHANGE-CAUSE
2         <none>
3         <none>
4         <none>

[root@k8smaster ~]# kubectl get rs -o wide #可以看到当前pod运行的镜像为v1
NAME                      DESIRED   CURRENT   READY     AGE       CONTAINERS   IMAGES                 SELECTOR
myapp-deploy-67f6f6b4dc   0         0         0         1h        myapp        ikubernetes/myapp:v2   app=myapp,pod-template-hash=2392926087,release=canary
myapp-deploy-69b47bc96d   5         5         5         1h        myapp        ikubernetes/myapp:v1   app=myapp,pod-template-hash=2560367528,release=canary
myapp-deploy-6bdcd6755d   0         0         0         27m       myapp        ikubernetes/myapp:v3   app=myapp,pod-template-hash=2687823118,release=canary

二、DaemonSet,其作用在于,在整个集群的每一个节点上只运行某个指定pod的一个并且只能是一个副本,或者只能是在集群中某些符合选择器的节点上每一个节点只运行一个指定的副本。用于实现系统级的管理功能,可以直接把节点上的某个目录作为存储卷关联至pod中让pod实现某些管理功能。比如EFK中的Filebeat

 45分46秒

  

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