K8S---YAML文件編寫

K8S—YAML文件編寫

一.YAML的介紹

1.Kubernetes支持YAML和JSON格式創建資源對象

2.JSON格式用於接口之間消息的傳遞

3.YAML格式用於配置和管理

4.YAML是一種簡潔的非標記性語言

5.語法格式：

縮進標識層級關係

不支持製表符縮進，使用空格縮進

通常開頭縮進兩個空格

字符後縮進一個空格，如冒號，逗號等

“—”表示YAML格式，一個文件的開始

“#”表示註釋

二.YAML文件詳解

1.查看api版本

[root@localhost k8s]# kubectl api-versions
admissionregistration.k8s.io/v1beta1
apiextensions.k8s.io/v1beta1
apiregistration.k8s.io/v1
apiregistration.k8s.io/v1beta1
apps/v1			//應用服務
apps/v1beta1		//測試版本
apps/v1beta2
authentication.k8s.io/v1
authentication.k8s.io/v1beta1
authorization.k8s.io/v1
authorization.k8s.io/v1beta1
autoscaling/v1		//彈性伸縮
autoscaling/v2beta1
autoscaling/v2beta2
batch/v1
batch/v1beta1
certificates.k8s.io/v1beta1
coordination.k8s.io/v1beta1
events.k8s.io/v1beta1
extensions/v1beta1
networking.k8s.io/v1
policy/v1beta1
rbac.authorization.k8s.io/v1		//權限控制
rbac.authorization.k8s.io/v1beta1
scheduling.k8s.io/v1beta1
storage.k8s.io/v1
storage.k8s.io/v1beta1
v1

2.自行編寫nginx的yaml文件（手動）

[root@localhost ~]# mkdir demo
[root@localhost ~]# cd demo/
[root@localhost demo]# vim nginx-deployment.yaml

apiVersion: apps/v1		//api版本
kind: Deployment		//指定類型，deployment表示控制器
metadata:		//定義資源屬性
  name: nginx-deployment	//資源名稱
  labels:		//資源標籤
    app: nginx
spec:		//資源內容
  replicas: 3		//副本
  selector:		//選擇器
    matchLabels:		//匹配標籤
      app: nginx		//匹配模板名稱
  template:		//從這開始往下，是pod的資源管理
    metadata:
      labels:
        app: nginx
    spec:		//定義容器模板
      containers:		//信息

      - name: nginx		//容器名
        image: nginx:1.15.4		//容器使用鏡像和版本
        ports:
        - containerPort: 80		//對外端口

3.使用yaml文件創建資源，並查看

[root@localhost demo]# kubectl create -f nginx-deployment.yaml
deployment.apps/nginx-deployment created
[root@localhost demo]# kubectl get pods
NAME                              READY   STATUS    RESTARTS   AGE
nginx-7697996758-ksqr7            1/1     Running   0          40m
nginx-7697996758-s52gb            1/1     Running   0          40m
nginx-7697996758-v9qzw            1/1     Running   0          40m
nginx-deployment-d55b94fd-99qxf   1/1     Running   0          58s
nginx-deployment-d55b94fd-bz76x   1/1     Running   0          58s
nginx-deployment-d55b94fd-tk27h   1/1     Running   0          58s

[root@localhost demo]# kubectl get deploy
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx              3         3         3            3           43m
nginx-deployment   3         3         3            3           4m12s

//下三個是剛創建的

4.創建service的yaml文件（手動）

[root@localhost demo]# vim nginx-service.yaml

apiVersion: v1		//版本
kind: Service		//類型  
metadata:		//元數據		
  name: nginx-service		//service名稱
  labels:		//標籤屬性
    app: nginx  
spec:		//詳情
  type: NodePort		//service的類型默認爲ClusterIP
  ports:		//端口

  - port: 80		//內部端口
    targetPort: 80		//需轉發的端口  
    selector:		//選擇器
    app: nginx		//pod資源名稱

5.使用yaml文件創建service

[root@localhost demo]# kubectl create -f nginx-service.yaml
service/nginx-service created
[root@localhost demo]# kubectl get svc
NAME            TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)        AGE
kubernetes      ClusterIP   10.0.0.1     <none>        443/TCP        4d22h
nginx-service   NodePort    10.0.0.83    <none>        80:47336/TCP   30s

//訪問查看

6.自動測試命令的正確性，並不執行創建（自動）

[root@localhost demo]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
deployment.apps/nginx-deployment created (dry run)		//此時，此命令可被執行

7.查看yaml文件格式

[root@localhost demo]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o yaml
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
apiVersion: apps/v1beta1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    run: nginx-deployment
  name: nginx-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      run: nginx-deployment
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        run: nginx-deployment
    spec:
      containers:
      - image: nginx
        name: nginx-deployment
        ports:
        - containerPort: 80
        resources: {}
status: {}

8.查看生成json格式

[root@localhost demo]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o json
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
{
    "kind": "Deployment",
    "apiVersion": "apps/v1beta1",
    "metadata": {
        "name": "nginx-deployment",
        "creationTimestamp": null,
        "labels": {
            "run": "nginx-deployment"
        }
    },
    "spec": {
        "replicas": 3,
        "selector": {
            "matchLabels": {
                "run": "nginx-deployment"
            }
        },
        "template": {
            "metadata": {
                "creationTimestamp": null,
                "labels": {
                    "run": "nginx-deployment"
                }
            },
            "spec": {
                "containers": [
                    {
                        "name": "nginx-deployment",
                        "image": "nginx",
                        "ports": [
                            {
                                "containerPort": 80
                            }
                        ],
                        "resources": {}
                    }
                ]
            }
        },
        "strategy": {}
    },
    "status": {}
}

9.把yaml文件格式導出，進行修改即可

[root@localhost demo]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o yaml > my-deployment.yaml
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
[root@localhost demo]# ls
my-deployment.yaml  nginx-deployment.yaml  nginx-service.yaml
[root@localhost demo]# vim my-deployment.yaml 

apiVersion: apps/v1beta1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    run: nginx-deployment
  name: nginx-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      run: nginx-deployment
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        run: nginx-deployment
    spec:
      containers:
      - image: nginx
        name: nginx-deployment
        ports:
        - containerPort: 80
        resources: {}
status: {}

10.將現有的資源生成yaml，並導出

//將現有的資源生成模板導出

[root@localhost demo]# kubectl get deploy/nginx
NAME    DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx   3         3         3            3           68m
[root@localhost demo]# kubectl get deploy/nginx --export -o yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  annotations:
    deployment.kubernetes.io/revision: "1"
  creationTimestamp: null
  generation: 1
  labels:
    run: nginx
  name: nginx
  selfLink: /apis/extensions/v1beta1/namespaces/default/deployments/nginx
spec:
  progressDeadlineSeconds: 600
  replicas: 3
  revisionHistoryLimit: 2
  selector:
    matchLabels:
      run: nginx
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        run: nginx
    spec:
      containers:
      - image: nginx:latest
        imagePullPolicy: Always
        name: nginx
        ports:
        - containerPort: 80
          protocol: TCP
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
            dnsPolicy: ClusterFirst
            restartPolicy: Always
            schedulerName: default-scheduler
            securityContext: {}
            terminationGracePeriodSeconds: 30
status: {}

//保存到文件中

[root@localhost demo]# kubectl get deploy/nginx --export -o yaml > my-deploy.yaml
[root@localhost demo]# ls
my-deployment.yaml  my-deploy.yaml  nginx-deployment.yaml  nginx-service.yaml

//查看字段幫助信息
[root@localhost demo]# kubectl explain pods.spec.containers