【k8s资源调度-Deployment】

1、标签和选择器

1.1 标签Label

配置文件：在各类资源的sepc.metadata.label 中进行配置
通过kubectl 命令行创建修改标签，语法如下
- 创建临时label：kubectl label po <资源名称> app=hello -n <命令空间（可不加）>
- 修改已经存在的label： kubectl label po <资源名称> app=hello -n <命令空间（可不加）> --overwrite
- 通过查看lable的时候修改label
  - selector 按照 label 单值查找节点： kubectl get po -A -l app=hello
  - 查看所有节点的labels ：kubectl get po --show-labels

## 创建pod
[root@k8s-master ~]# kubectl create -f nginx-po.yml
pod/nginx-liveness-po created# 查看pod状态
[root@k8s-master ~]# kubectl get po  nginx-liveness-po
NAME                READY   STATUS    RESTARTS   AGE
nginx-liveness-po   1/1     Running   0          51s# 查看pod状态，显示label信息
[root@k8s-master ~]# kubectl get po  nginx-liveness-po --show-labels
NAME                READY   STATUS    RESTARTS   AGE   LABELS
nginx-liveness-po   1/1     Running   0          68s   test=l.0.0,type=app# 临时给pod添加label
[root@k8s-master ~]# kubectl label po nginx-liveness-po  auth=xiaobai
pod/nginx-liveness-po labeled[root@k8s-master ~]# kubectl get po  nginx-liveness-po --show-labels
NAME                READY   STATUS    RESTARTS   AGE    LABELS
nginx-liveness-po   1/1     Running   0          105s   auth=xiaobai,test=l.0.0,type=app# 修改pod的label，但是不加 --overwrite 会提示失败，需要加 --overweite
[root@k8s-master ~]# kubectl label po nginx-liveness-po  auth=xiaohong
error: 'auth' already has a value (xiaobai), and --overwrite is false
[root@k8s-master ~]# kubectl label po nginx-liveness-po  auth=xiaohong   --overwrite
pod/nginx-liveness-po labeled# 修改label属性已经更改
[root@k8s-master ~]# kubectl get po  nginx-liveness-po --show-labels
NAME                READY   STATUS    RESTARTS   AGE    LABELS
nginx-liveness-po   1/1     Running   0          2m3s   auth=xiaohong,test=l.0.0,type=app# 通过单个labe信息查找pod
[root@k8s-master ~]# kubectl get po  -A  -l  type=app
NAMESPACE   NAME                READY   STATUS    RESTARTS   AGE
default     nginx-liveness-po   1/1     Running   0          8m27s

1.2 选择器Seletor

通过yaml配置文件，在各对象的配置 spec.seletor 或其他可以写selector的属性中编写。
通过命令行模式，语法如下
- 匹配但个值，查找app=hello的pod：kubectl get po -A -I app=hello
- 匹配多个值：kubectl get po -A -I ‘k8s-app in (metrics-server,kubernetes-dashboard)’
- 查找version!=1 and app=nginx的pod信息：kubectl get po -I version!=1,app=nginx


# 单值匹配的时候
[root@k8s-master ~]# kubectl get po  -A  -l  type=app --show-labels
NAMESPACE   NAME                READY   STATUS    RESTARTS   AGE   LABELS
default     nginx-liveness-po   1/1     Running   0          18m   auth=xiaohong,test=l.0.0,type=app# 显示所有的pod的label信息
[root@k8s-master ~]# kubectl get po  -A  --show-labels
NAMESPACE      NAME                                 READY   STATUS    RESTARTS      AGE     LABELS
default        nginx-liveness-po                    1/1     Running   0             18m     auth=xiaohong,test=l.0.0,type=app
kube-flannel   kube-flannel-ds-glkkb                1/1     Running   4 (24h ago)   3d19h   app=flannel,controller-revision-hash=7cfb6d964b,pod-template-generation=1,tier=node
kube-flannel   kube-flannel-ds-pdmtw                1/1     Running   1 (24h ago)   44h     app=flannel,controller-revision-hash=7cfb6d964b,pod-template-generation=1,tier=node
kube-flannel   kube-flannel-ds-tpm8x                1/1     Running   2 (24h ago)   3d19h   app=flannel,controller-revision-hash=7cfb6d964b,pod-template-generation=1,tier=node
kube-system    coredns-c676cc86f-pdsl6              1/1     Running   3 (24h ago)   2d7h    k8s-app=kube-dns,pod-template-hash=c676cc86f
kube-system    coredns-c676cc86f-q7hcw              1/1     Running   1 (24h ago)   2d7h    k8s-app=kube-dns,pod-template-hash=c676cc86f
kube-system    etcd-k8s-master                      1/1     Running   2 (24h ago)   3d20h   component=etcd,tier=control-plane
kube-system    kube-apiserver-k8s-master            1/1     Running   3 (24h ago)   3d20h   component=kube-apiserver,tier=control-plane
kube-system    kube-controller-manager-k8s-master   1/1     Running   4 (24h ago)   3d20h   component=kube-controller-manager,tier=control-plane
kube-system    kube-proxy-n2w92                     1/1     Running   4 (24h ago)   3d19h   controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system    kube-proxy-p8fhs                     1/1     Running   1 (24h ago)   44h     controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system    kube-proxy-xtllb                     1/1     Running   2 (24h ago)   3d20h   controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system    kube-scheduler-k8s-master            1/1     Running   4 (24h ago)   3d20h   component=kube-scheduler,tier=control-plane# 匹配单个值 app!=flannel
[root@k8s-master ~]# kubectl get po  -A   -l app!=flannel
NAMESPACE     NAME                                 READY   STATUS    RESTARTS      AGE
default       nginx-liveness-po                    1/1     Running   0             19m
kube-system   coredns-c676cc86f-pdsl6              1/1     Running   3 (24h ago)   2d7h
kube-system   coredns-c676cc86f-q7hcw              1/1     Running   1 (24h ago)   2d7h
kube-system   etcd-k8s-master                      1/1     Running   2 (24h ago)   3d20h
kube-system   kube-apiserver-k8s-master            1/1     Running   3 (24h ago)   3d20h
kube-system   kube-controller-manager-k8s-master   1/1     Running   4 (24h ago)   3d20h
kube-system   kube-proxy-n2w92                     1/1     Running   4 (24h ago)   3d19h
kube-system   kube-proxy-p8fhs                     1/1     Running   1 (24h ago)   44h
kube-system   kube-proxy-xtllb                     1/1     Running   2 (24h ago)   3d20h
kube-system   kube-scheduler-k8s-master            1/1     Running   4 (24h ago)   3d20h[root@k8s-master ~]# kubectl get po  -A   -l app!=flannel --show-labels
NAMESPACE     NAME                                 READY   STATUS    RESTARTS      AGE     LABELS
default       nginx-liveness-po                    1/1     Running   0             19m     auth=xiaohong,test=l.0.0,type=app
kube-system   coredns-c676cc86f-pdsl6              1/1     Running   3 (24h ago)   2d7h    k8s-app=kube-dns,pod-template-hash=c676cc86f
kube-system   coredns-c676cc86f-q7hcw              1/1     Running   1 (24h ago)   2d7h    k8s-app=kube-dns,pod-template-hash=c676cc86f
kube-system   etcd-k8s-master                      1/1     Running   2 (24h ago)   3d20h   component=etcd,tier=control-plane
kube-system   kube-apiserver-k8s-master            1/1     Running   3 (24h ago)   3d20h   component=kube-apiserver,tier=control-plane
kube-system   kube-controller-manager-k8s-master   1/1     Running   4 (24h ago)   3d20h   component=kube-controller-manager,tier=control-plane
kube-system   kube-proxy-n2w92                     1/1     Running   4 (24h ago)   3d19h   controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system   kube-proxy-p8fhs                     1/1     Running   1 (24h ago)   44h     controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system   kube-proxy-xtllb                     1/1     Running   2 (24h ago)   3d20h   controller-revision-hash=dd4c999cf,k8s-app=kube-proxy,pod-template-generation=1
kube-system   kube-scheduler-k8s-master            1/1     Running   4 (24h ago)   3d20h   component=kube-scheduler,tier=control-plane# 多值匹配
[root@k8s-master ~]# kubectl get po  -A   -l app!=flannel,test=1.0.0 --show-labels
No resources found# 多值匹配，多值匹配是“与”的关系，不是“或”的关系
[root@k8s-master ~]# kubectl get po  -A   -l app!=flannel,type=app  --show-labels
NAMESPACE   NAME                READY   STATUS    RESTARTS   AGE   LABELS
default     nginx-liveness-po   1/1     Running   0          20m   auth=xiaohong,test=l.0.0,type=app

2、部署对象Deployment（无状态应用）

在这里插入图片描述

2.1 创建deploy

2.1.1 通过命令行创建一个deployment

# 创建一个deployment
[root@k8s-master ~]# kubectl create deploy nginx-deploy --image=nginx:1.20
deployment.apps/nginx-deploy created

创建一个deployment
使用命令行模式：kubectl create deploy nginx-deploy --image=nginx:1.20
或执行 kubectl create -f xxx.yaml --record
-record会在annotation中记录当前命令创建或升级了资源，后续可以查看做过哪变动操作。

2.1.2 查看deployment 信息

通过kubectl get 查看deployment，可以使用deployment，也可以用deploy

# 通过kubectl get 查看deployment，可以使用deployment，也可以用deploy
[root@k8s-master ~]# kubectl  get deployments
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   1/1     1            1           10s[root@k8s-master ~]# kubectl  get deploy
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   1/1     1            1           14s

2.1.3 查看replicasets 信息

由于创建的deployment资源包含 replicasets信息（replicasets是可以自动扩容和缩容），可以查看到 replicasets的名字中包含deploy资源的名字信息

# 由于deployment包含 replicasets（replicasets是可以自动扩容和缩容），可以查看到 replicasets的名字中包含deploy的名字信息 
[root@k8s-master ~]# kubectl  get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-86b7d8c46d   1         1         1       18s[root@k8s-master ~]# kubectl  get replicasets.apps
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-86b7d8c46d   1         1         1       38s

2.1.4 查看pod 信息

可以查看到deployment创建的pod种包含 replicasets 资源的名字信息

# 下面的pod可以查看到pod的名字包含 replicasets 名字的信息
[root@k8s-master ~]# kubectl  get po
NAME                            READY   STATUS    RESTARTS   AGE
nginx-deploy-86b7d8c46d-78rj9   1/1     Running   0          46s

2.1.5 通过命令行模式创建的deployment 生成 yaml信息

# 通过创建好的deploy生成yaml文件 
[root@k8s-master ~]# kubectl get deploy nginx-deploy  -o yaml
apiVersion: apps/v1
kind: Deployment
metadata:annotations:deployment.kubernetes.io/revision: "1"creationTimestamp: "2024-02-23T10:59:04Z"generation: 1labels:app: nginx-deployname: nginx-deploynamespace: defaultresourceVersion: "235341"uid: def47aae-13f7-415a-a9d1-18ef72e5a925
spec:progressDeadlineSeconds: 600replicas: 1revisionHistoryLimit: 10selector:matchLabels:app: nginx-deploystrategy:rollingUpdate:maxSurge: 25%maxUnavailable: 25%type: RollingUpdatetemplate:metadata:creationTimestamp: nulllabels:app: nginx-deployspec:containers:- image: nginx:1.20imagePullPolicy: IfNotPresentname: nginxresources: {}terminationMessagePath: /dev/termination-logterminationMessagePolicy: FilednsPolicy: ClusterFirstrestartPolicy: AlwaysschedulerName: default-schedulersecurityContext: {}terminationGracePeriodSeconds: 30
status:availableReplicas: 1conditions:- lastTransitionTime: "2024-02-23T10:59:05Z"lastUpdateTime: "2024-02-23T10:59:05Z"message: Deployment has minimum availability.reason: MinimumReplicasAvailablestatus: "True"type: Available- lastTransitionTime: "2024-02-23T10:59:04Z"lastUpdateTime: "2024-02-23T10:59:05Z"message: ReplicaSet "nginx-deploy-86b7d8c46d" has successfully progressed.reason: NewReplicaSetAvailablestatus: "True"type: ProgressingobservedGeneration: 1readyReplicas: 1replicas: 1updatedReplicas: 1

2.1.6 查看po、rs、deploy中所有的label信息

通过以下信息，可以查看到：
deploy、rs、pod种都包含同一个label信息：app=nginx-deploy；
rs和pod中同时还有一个相同的pod标签信息：pod-template-hash=86b7d8c46d，这个标签信息就是为了我们能更方便的动态创建pod使用。

[root@k8s-master ~]# kubectl get po,rs,deploy  --show-labels
NAME                                READY   STATUS    RESTARTS   AGE   LABELS
pod/nginx-deploy-86b7d8c46d-78rj9   1/1     Running   0          30m   app=nginx-deploy,pod-template-hash=86b7d8c46dNAME                                      DESIRED   CURRENT   READY   AGE   LABELS
replicaset.apps/nginx-deploy-86b7d8c46d   1         1         1       30m   app=nginx-deploy,pod-template-hash=86b7d8c46dNAME                           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
deployment.apps/nginx-deploy   1/1     1            1           30m   app=nginx-deploy

2.1.7 通过（2.1.5）中生成的yaml信息创建yaml文件

通过命令行创建的deployment信息生成yaml信息，根据我们所需信息来创建yaml文件

apiVersion: apps/v1  # deployment api版本
kind: Deployment    # 资源类型为 Deployment
metadata:  # 原信息labels:  # 标签app: nginx-deploy  # 具体的标签信息：app=nginx-deploy   key: value 配置形式name: nginx-deploy   # deployment的名字namespace: default   # 所在的命名空间
spec:replicas: 1   # 期望副本数revisionHistoryLimit: 10   # 进行滚动更新后，保留的历史版本数量selector:  # 选择器，用于找到匹配的RSmatchLabels:  # 按照标签匹配app: nginx-deploy   # 匹配的标签strategy:   #更新策略rollingUpdate:  # 滚动更新配置maxSurge: 25%  # 滚动更新时，更新的个数最多超过多少个期望副本数，或者比例maxUnavailable: 25%  # 进行滚动更新时，最大不可用比例更新比例，表示在所有副本数中，最多可以有多少个不更新成功type: RollingUpdate  # 更新类型，采用滚动更新template:   # pod 模板metadata:  # pod模板的元信息labels:   # pod模板的标签app: nginx-deploy   # pod模板的标签信息spec:      # pod 期望信息containers:    # pod 的容器信息- image: nginx:1.20    # 镜像信息imagePullPolicy: IfNotPresent   # 镜像拉取策略name: nginx        # 容器名字restartPolicy: Always   # pod的重启策略terminationGracePeriodSeconds: 30   # pod的过期时间

2.2 滚动更新

只有修改了deployment 配置文件文件中的template中的属性后，才会触发滚动更新操作

2.2.1 修改deploy中的其他属性查看pod是否会更新

[root@k8s-master ~]# kubectl get deployments --show-labels
NAME           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
nginx-deploy   1/1     1            1           44m   app=nginx-deploy[root@k8s-master ~]# kubectl edit deployments nginx-deploy
deployment.apps/nginx-deploy edited

在这里插入图片描述

可以通过下面新的看到我们的deploy更新并没有导致pod更新，只是把新加的标签给更新到了deploy上。

[root@k8s-master ~]# kubectl get deployments --show-labels
NAME           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
nginx-deploy   1/1     1            1           49m   app=nginx-deploy,new-version=test#  rs和pod并没有这个标签信息
[root@k8s-master ~]# kubectl get deployments,rs,pod  --show-labels
NAME                           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
deployment.apps/nginx-deploy   1/1     1            1           51m   app=nginx-deploy,new-version=testNAME                                      DESIRED   CURRENT   READY   AGE   LABELS
replicaset.apps/nginx-deploy-86b7d8c46d   1         1         1       51m   app=nginx-deploy,pod-template-hash=86b7d8c46dNAME                                READY   STATUS    RESTARTS   AGE   LABELS
pod/nginx-deploy-86b7d8c46d-78rj9   1/1     Running   0          51m   app=nginx-deploy,pod-template-hash=86b7d8c46d

在这里插入图片描述

2.2.2 修改这个deploy的副本数

在这里插入图片描述

[root@k8s-master ~]# kubectl get deploy nginx-deploy --show-labels
NAME           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
nginx-deploy   3/3     3            3           55m   app=nginx-deploy,new-version=test
[root@k8s-master ~]# kubectl describe  deployments  nginx-deploy
Name:                   nginx-deploy
Namespace:              default
CreationTimestamp:      Fri, 23 Feb 2024 18:59:04 +0800
Labels:                 app=nginx-deploynew-version=test
Annotations:            deployment.kubernetes.io/revision: 1
Selector:               app=nginx-deploy
Replicas:               3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge
Pod Template:Labels:  app=nginx-deployContainers:nginx:Image:        nginx:1.20Port:         <none>Host Port:    <none>Environment:  <none>Mounts:       <none>Volumes:        <none>
Conditions:Type           Status  Reason----           ------  ------Progressing    True    NewReplicaSetAvailableAvailable      True    MinimumReplicasAvailable
OldReplicaSets:  <none>
NewReplicaSet:   nginx-deploy-86b7d8c46d (3/3 replicas created)
Events:Type    Reason             Age   From                   Message----    ------             ----  ----                   -------Normal  ScalingReplicaSet  55m   deployment-controller  Scaled up replica set nginx-deploy-86b7d8c46d to 1Normal  ScalingReplicaSet  27s   deployment-controller  Scaled up replica set nginx-deploy-86b7d8c46d to 3 from 1
[root@k8s-master ~]#

通过增加副本数后，我们可以看到deploy变为了3，rs为1，pod为3，pod的模版使用的都是同一个模版。

[root@k8s-master ~]# kubectl get deployments,rs,po  --show-labels
NAME                           READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
deployment.apps/nginx-deploy   3/3     3            3           57m   app=nginx-deploy,new-version=testNAME                                      DESIRED   CURRENT   READY   AGE   LABELS
replicaset.apps/nginx-deploy-86b7d8c46d   3         3         3       57m   app=nginx-deploy,pod-template-hash=86b7d8c46dNAME                                READY   STATUS    RESTARTS   AGE   LABELS
pod/nginx-deploy-86b7d8c46d-6cf95   1/1     Running   0          93s   app=nginx-deploy,pod-template-hash=86b7d8c46d
pod/nginx-deploy-86b7d8c46d-78rj9   1/1     Running   0          57m   app=nginx-deploy,pod-template-hash=86b7d8c46d
pod/nginx-deploy-86b7d8c46d-vjncw   1/1     Running   0          93s   app=nginx-deploy,pod-template-hash=86b7d8c46d

2.2.3 通过edit选项编辑template属性后我们看看会发生那些变化

在这里插入图片描述
通过实时监控deploy的时候可以看到deploy的变化

[root@k8s-master ~]# kubectl get deployments.apps  nginx-deploy  -w
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   3/3     3            3           61m
nginx-deploy   3/3     3            3           61m
nginx-deploy   3/3     3            3           61m
nginx-deploy   3/3     0            3           61m
nginx-deploy   3/3     1            3           61m
nginx-deploy   4/3     1            4           62m
nginx-deploy   3/3     1            3           62m
nginx-deploy   3/3     2            3           62m
nginx-deploy   4/3     2            4           62m
nginx-deploy   3/3     2            3           62m
nginx-deploy   3/3     3            3           62m
nginx-deploy   4/3     3            4           62m
nginx-deploy   3/3     3            3           62m# 通过这个命令可以看到更新的状态为成功了
[root@k8s-master ~]# kubectl rollout status deployment nginx-deploy
deployment "nginx-deploy" successfully rolled out

2.2.4 修改set选项编辑刚才的镜像信息看看更新如何

[root@k8s-master ~]# kubectl set  image  deployment/nginx-deploy   nginx=nginx:1.20
deployment.apps/nginx-deploy image updated[root@k8s-master ~]# kubectl get deployments.apps  nginx-deploy  -w
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   3/3     3            3           72m
nginx-deploy   3/3     3            3           72m
nginx-deploy   3/3     3            3           72m
nginx-deploy   3/3     0            3           72m
nginx-deploy   3/3     1            3           72m
nginx-deploy   4/3     1            4           72m
nginx-deploy   3/3     1            3           72m
nginx-deploy   3/3     2            3           72m
nginx-deploy   4/3     2            4           72m
nginx-deploy   3/3     2            3           72m
nginx-deploy   3/3     3            3           72m
nginx-deploy   4/3     3            4           72m
nginx-deploy   3/3     3            3           72m

在这里插入图片描述

通过如下信息，可以看到新的nginx pod信息可以看到他滚动更新到刚开始的rs信息

[root@k8s-master ~]# kubectl get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-6bf65c4445   0         0         0       17m
nginx-deploy-86b7d8c46d   3         3         3       79m
[root@k8s-master ~]# kubectl get  pod
NAME                            READY   STATUS    RESTARTS   AGE
nginx-deploy-86b7d8c46d-4s98c   1/1     Running   0          7m17s
nginx-deploy-86b7d8c46d-7s9gz   1/1     Running   0          7m19s
nginx-deploy-86b7d8c46d-w8ljk   1/1     Running   0          7m15s

2.3 回滚操作

有时候你可能想回退一个Deployment，例如，当Deployment不稳定时，比如一直crash looping。
默认侍况下，kubernetes会在系统中保存前两次的Deployment的rollout历史记录，以便你可以随时会退（你可以修改revisionhistory limit来更改保存的revision数)，

2.3.1 通过set选项修改一个错误的images信息

[root@k8s-master ~]# kubectl set  image  deployment/nginx-deploy   nginx=nginx:1.200
deployment.apps/nginx-deploy image updated# 可以看到一个更新的这个nginx的状态是ImagePullBackOff
[root@k8s-master ~]# kubectl get pod  -w
NAME                            READY   STATUS             RESTARTS   AGE
nginx-deploy-85bc5c8fdb-h4rmn   0/1     ImagePullBackOff   0          83s
nginx-deploy-86b7d8c46d-4s98c   1/1     Running            0          25m
nginx-deploy-86b7d8c46d-7s9gz   1/1     Running            0          25m
nginx-deploy-86b7d8c46d-w8ljk   1/1     Running            0          25m

在这里插入图片描述

使用命令：kubectl describe pod nginx-deploy-85bc5c8fdb-h4rmn 可以查看到这个新的pod信息
在这里插入图片描述

2.3.2 通过edit选项查看这个deploy的信息

在这里插入图片描述

2.3.3 查看历史的版本信息

[root@k8s-master ~]# kubectl rollout history  deployment/nginx-deploy  --revision=0
deployment.apps/nginx-deploy
REVISION  CHANGE-CAUSE
2         <none>
3         <none>
4         <none>

2.3.4 查看历史更新的具体信息

[root@k8s-master ~]# kubectl rollout history  deployment/nginx-deploy  --revision=4
deployment.apps/nginx-deploy with revision #4
Pod Template:Labels:	app=nginx-deploypod-template-hash=85bc5c8fdbContainers:nginx:Image:	nginx:1.200Port:	<none>Host Port:	<none>Environment:	<none>Mounts:	<none>Volumes:	<none>[root@k8s-master ~]# kubectl rollout history  deployment/nginx-deploy  --revision=3
deployment.apps/nginx-deploy with revision #3
Pod Template:Labels:	app=nginx-deploypod-template-hash=86b7d8c46dContainers:nginx:Image:	nginx:1.20Port:	<none>Host Port:	<none>Environment:	<none>Mounts:	<none>Volumes:	<none>[root@k8s-master ~]# kubectl rollout history  deployment/nginx-deploy  --revision=2
deployment.apps/nginx-deploy with revision #2
Pod Template:Labels:	app=nginx-deploypod-template-hash=6bf65c4445Containers:nginx:Image:	nginx:1.21Port:	<none>Host Port:	<none>Environment:	<none>Mounts:	<none>Volumes:	<none>

2.3.5 回滚为revision=3的版本

[root@k8s-master ~]# kubectl rollout undo  deployment/nginx-deploy   --to-revision=3
deployment.apps/nginx-deploy rolled back[root@k8s-master ~]#   kubectl  rollout  status  deployments.apps  nginx-deploy
deployment "nginx-deploy" successfully rolled out

在这里插入图片描述
如下已经回滚为了revision=3的版本。

[root@k8s-master ~]# kubectl describe deployments nginx-deploy
Name:                   nginx-deploy
Namespace:              default
CreationTimestamp:      Fri, 23 Feb 2024 18:59:04 +0800
Labels:                 app=nginx-deploynew-version=test
Annotations:            deployment.kubernetes.io/revision: 5
Selector:               app=nginx-deploy
Replicas:               3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge
Pod Template:Labels:  app=nginx-deployContainers:nginx:Image:        nginx:1.20Port:         <none>Host Port:    <none>Environment:  <none>Mounts:       <none>Volumes:        <none>
Conditions:Type           Status  Reason----           ------  ------Available      True    MinimumReplicasAvailableProgressing    True    NewReplicaSetAvailable
OldReplicaSets:  <none>
NewReplicaSet:   nginx-deploy-86b7d8c46d (3/3 replicas created)
Events:Type    Reason             Age                From                   Message----    ------             ----               ----                   -------Normal  ScalingReplicaSet  57m                deployment-controller  Scaled up replica set nginx-deploy-86b7d8c46d to 3 from 1Normal  ScalingReplicaSet  51m                deployment-controller  Scaled up replica set nginx-deploy-6bf65c4445 to 1Normal  ScalingReplicaSet  50m                deployment-controller  Scaled down replica set nginx-deploy-86b7d8c46d to 2 from 3Normal  ScalingReplicaSet  50m                deployment-controller  Scaled up replica set nginx-deploy-6bf65c4445 to 2 from 1Normal  ScalingReplicaSet  49m                deployment-controller  Scaled down replica set nginx-deploy-86b7d8c46d to 1 from 2Normal  ScalingReplicaSet  49m                deployment-controller  Scaled up replica set nginx-deploy-6bf65c4445 to 3 from 2Normal  ScalingReplicaSet  49m                deployment-controller  Scaled down replica set nginx-deploy-86b7d8c46d to 0 from 1Normal  ScalingReplicaSet  40m                deployment-controller  Scaled up replica set nginx-deploy-86b7d8c46d to 1 from 0Normal  ScalingReplicaSet  40m                deployment-controller  Scaled down replica set nginx-deploy-6bf65c4445 to 2 from 3Normal  ScalingReplicaSet  40m (x4 over 40m)  deployment-controller  (combined from similar events): Scaled down replica set nginx-deploy-6bf65c4445 to 0 from 1Normal  ScalingReplicaSet  16m                deployment-controller  Scaled up replica set nginx-deploy-85bc5c8fdb to 1Normal  ScalingReplicaSet  116s               deployment-controller  Scaled down replica set nginx-deploy-85bc5c8fdb to 0 from 1

2.3.6 为啥可以回退为revision=3呢？

可以通过设置，spec.revisonHistoryLimit来指定deployment保留多少revision。如果revisonHistoryLimit设置为0，则不允许deployment回退了。

2.4 扩容和缩容

扩缩容命令： kubectl scale --replicas=6 deployment nginx-deploy
扩容和缩容一样，只需要通过–replicas 指定数量即可

2.4.1 扩容

# 目前有3个pod，扩容到6个
[root@k8s-master ~]# kubectl scale --replicas=6 deployment nginx-deploy
deployment.apps/nginx-deploy scaled
[root@k8s-master ~]# kubectl get deployments nginx-deploy
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   6/6     6            6           5h43m
[root@k8s-master ~]# kubectl get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-6bf65c4445   0         0         0       4h42m
nginx-deploy-85bc5c8fdb   0         0         0       4h7m
nginx-deploy-86b7d8c46d   6         6         6       5h43m
[root@k8s-master ~]# kubectl get pod
NAME                            READY   STATUS    RESTARTS   AGE
nginx-deploy-86b7d8c46d-4s98c   1/1     Running   0          4h31m
nginx-deploy-86b7d8c46d-7s9gz   1/1     Running   0          4h31m
nginx-deploy-86b7d8c46d-n2m6j   1/1     Running   0          33s
nginx-deploy-86b7d8c46d-w8ljk   1/1     Running   0          4h31m
nginx-deploy-86b7d8c46d-wgdnv   1/1     Running   0          33s
nginx-deploy-86b7d8c46d-z86rx   1/1     Running   0          33s

2.4.1 缩容

# 缩容，有6个pod，现在缩容到4个pod
[root@k8s-master ~]# kubectl scale --replicas=4  deployment nginx-deploy
deployment.apps/nginx-deploy scaled
[root@k8s-master ~]# kubectl get deployments nginx-deploy
NAME           READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deploy   4/4     4            4           5h45m
[root@k8s-master ~]# kubectl get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-6bf65c4445   0         0         0       4h44m
nginx-deploy-85bc5c8fdb   0         0         0       4h9m
nginx-deploy-86b7d8c46d   4         4         4       5h45m
[root@k8s-master ~]# kubectl get pod  -o wide
NAME                            READY   STATUS    RESTARTS   AGE     IP          NODE          NOMINATED NODE   READINESS GATES
nginx-deploy-86b7d8c46d-4s98c   1/1     Running   0          4h33m   10.2.2.12   k8s-node-01   <none>           <none>
nginx-deploy-86b7d8c46d-7s9gz   1/1     Running   0          4h33m   10.2.1.28   k8s-node-02   <none>           <none>
nginx-deploy-86b7d8c46d-w8ljk   1/1     Running   0          4h33m   10.2.1.29   k8s-node-02   <none>           <none>
nginx-deploy-86b7d8c46d-z86rx   1/1     Running   0          2m33s   10.2.2.14   k8s-node-01   <none>           <none>

2.5 暂停和恢复

由于每次对pod 的 template中的信息发生修改后，都会触发更新deployment操作，那么此时如果频繁修改信息，就会产生多次更新，而实际上只需要执行最后一次更新即可，当出现此类情况时我们就可以暂停deployment的 rollout。

2.5.1 给template添加一个最小cpu和内存的参数

在这里插入图片描述

2.5.2 暂停deploy更新

通过kubectl rollout pause deployment <name> 就可以实现暂停，直到你下次恢复后才会继续进行滚动更新。

# 暂时deploy更新
[root@k8s-master ~]# kubectl rollout pause deployment  nginx-deploy
deployment.apps/nginx-deploy paused

2.5.3 再次更新template，给cpu和内存添加一个最大参数

在这里插入图片描述

这次更新过之后，rs信息和pod信息都没有发生改变，是由于我们暂停了deploy的更新

[root@k8s-master ~]# kubectl edit  deploy  nginx-deploy
deployment.apps/nginx-deploy edited[root@k8s-master ~]# kubectl get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-6bf65c4445   0         0         0       5h7m
nginx-deploy-6dc7697cfb   3         3         3       8m33s
nginx-deploy-85bc5c8fdb   0         0         0       4h32m
nginx-deploy-86b7d8c46d   0         0         0       6h8m
[root@k8s-master ~]# kubectl get pod
NAME                            READY   STATUS    RESTARTS   AGE
nginx-deploy-6dc7697cfb-6p9mj   1/1     Running   0          8m38s
nginx-deploy-6dc7697cfb-lc472   1/1     Running   0          8m37s
nginx-deploy-6dc7697cfb-w295s   1/1     Running   0          8m35s

2.5.4 查看更新信息

通过下面的信息，可以看到刚才添加cpu和内存参数在更新历史列表里面没有显示，说明我们的deploy没有更新

[root@k8s-master ~]# kubectl rollout history  deployment nginx-deploy  --revision=0
deployment.apps/nginx-deploy
REVISION  CHANGE-CAUSE
2         <none>
4         <none>
5         <none>
6         <none>[root@k8s-master ~]# kubectl rollout history  deployment nginx-deploy  --revision=6
deployment.apps/nginx-deploy with revision #6
Pod Template:Labels:	app=nginx-deploypod-template-hash=6dc7697cfbContainers:nginx:Image:	nginx:1.20Port:	<none>Host Port:	<none>Requests:cpu:	100mmemory:	128MiEnvironment:	<none>Mounts:	<none>Volumes:	<none>

2.5.5 恢复deploy的更新

启动deploy的更新


[root@k8s-master ~]# kubectl rollout resume   deployment nginx-deploy
deployment.apps/nginx-deploy resumed

这里 rs 已经发生了改变

[root@k8s-master ~]# kubectl get rs
NAME                      DESIRED   CURRENT   READY   AGE
nginx-deploy-57bf686b9d   3         3         3       12s
nginx-deploy-6bf65c4445   0         0         0       5h15m
nginx-deploy-6dc7697cfb   0         0         0       17m
nginx-deploy-85bc5c8fdb   0         0         0       4h41m
nginx-deploy-86b7d8c46d   0         0         0       6h17m

刚才查询的历史更新版本只有4个，现在又多了一个

[root@k8s-master ~]# kubectl rollout history deployment nginx-deploy --revision=0
deployment.apps/nginx-deploy
REVISION  CHANGE-CAUSE
2         <none>
4         <none>
5         <none>
6         <none>
7         <none>

通过历史更新版本信息可以看到，我们添加的最大cpu和内存参数都发生了改变。

[root@k8s-master ~]# kubectl rollout history deployment nginx-deploy --revision=7
deployment.apps/nginx-deploy with revision #7
Pod Template:Labels:	app=nginx-deploypod-template-hash=57bf686b9dContainers:nginx:Image:	nginx:1.20Port:	<none>Host Port:	<none>Limits:cpu:	500mmemory:	512MiRequests:cpu:	100mmemory:	128MiEnvironment:	<none>Mounts:	<none>Volumes:	<none>

2.6 配置文件（部署无状态服务nginx的yaml文件）

[root@k8s-master ~]# cat nginx-deploy.yaml
apiVersion: apps/v1  # deployment api版本
kind: Deployment    # 资源类型为 Deployment
metadata:  # 原信息labels:  # 标签app: nginx-deploy  # 具体的标签信息：app=nginx-deploy   key: value 配置形式name: nginx-deploy   # deployment的名字namespace: default   # 所在的命名空间
spec:replicas: 1   # 期望副本数revisionHistoryLimit: 10   # 进行滚动更新后，保留的历史版本数量selector:  # 选择器，用于找到匹配的RSmatchLabels:  # 按照标签匹配app: nginx-deploy   # 匹配的标签strategy:   #更新策略rollingUpdate:  # 滚动更新配置maxSurge: 25%  # 滚动更新时，更新的个数最多超过多少个期望副本数，或者比例maxUnavailable: 25%  # 进行滚动更新时，最大不可用比例更新比例，表示在所有副本数中，最多可以有多少个不更新成功type: RollingUpdate  # 更新类型，采用滚动更新template:   # pod 模板metadata:  # pod模板的元信息labels:   # pod模板的标签app: nginx-deploy   # pod模板的标签信息spec:      # pod 期望信息containers:    # pod 的容器信息- image: nginx:1.20    # 镜像信息imagePullPolicy: IfNotPresent   # 镜像拉取策略name: nginx        # 容器名字restartPolicy: Always   # pod的重启策略terminationGracePeriodSeconds: 30   # pod的过期时间