k8s-YAML配置文件你还不会？？

YAML是专门用来写配置文件的语言，非常简洁和强大，使用比json更方便。它实质上是一种通用的数据串行化格式。

YAML语法规则：

• 大小写敏感
• 使用缩进表示层级关系
• 缩进时不允许使用Tal键，只允许使用空格
• 缩进的空格数目不重要，只要相同层级的元素左侧对齐即可
• ”#” 表示注释，从这个字符一直到行尾，都会被解析器忽略

在Kubernetes中，只需要知道两种结构类型即可：

• Lists
• Maps

示例

• 查看当前kubenetes可以用的apiVersios版本

[root@master ~]# kubectl api-versions
admissionregistration.k8s.io/v1beta1
apiextensions.k8s.io/v1beta1
apiregistration.k8s.io/v1
apiregistration.k8s.io/v1beta1
apps/v1          '//正式版本'
apps/v1beta1     '//测试版本'
apps/v1beta2
authentication.k8s.io/v1
authentication.k8s.io/v1beta1
authorization.k8s.io/v1
authorization.k8s.io/v1beta1
autoscaling/v1
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             '网络资源'
policy/v1beta1
rbac.authorization.k8s.io/v1     '权限控制资源'
rbac.authorization.k8s.io/v1beta1
scheduling.k8s.io/v1beta1        '调度资源'
storage.k8s.io/v1                '存储资源'
storage.k8s.io/v1beta1
v1

1、使用TAML文件创建资源对象

1.11：编辑测试文件

[root@master ~]# mkdir shuai    '//创建资源目录'
[root@master ~]# cd shuai/

[root@master shuai]# vim nginx-delpoy.yaml

apiVersion: apps/v1         '//api版本标签'
kind: Deployment            '//定义资源类型、角色，deployment是控制器'
metadata:                   '//定义资源的元数据'
  name: nginx-deployment    '//定义资源的名称，在同一个namesapce中必须唯一'
  labels:                   '//定义资源的标签'
    app: nginx
spec:                       '定义容器模板'
  replicas: 3               '//定义副本数量'
  selector:                 '//选择器'
    matchLabels:            '//匹配的标签'
      app: nginx            '//匹配模板名称'
  template:                 '//模板'
    metadata:
      labels:
        app: nginx
    spec:
      containers:           '//定义容器信息'
      - name: nginx         '//-：表示参数，容器名，与标签名要相同'
        image: nginx:1.15.4 '//容器使用的镜像以及版本'
        ports:
        - containerPort: 80  '//定义容器的对外端口'
        
apiVersion：此处值是v1，这个版本号需要根据安装的Kubernetes版本和资源类型进行变化，记住不是写死的。
kind：此处创建的是Pod，根据实际情况，此处资源类型可以是Deployment、Job、Ingress、Service等。
metadata：包含Pod的一些meta信息，比如名称、namespace、标签等信息。
spe：包括一些container，storage，volume以及其他Kubernetes需要的参数，以及诸如是否在容器失败时重新启动容器的属性。可在特定Kubernetes API找到完整的Kubernetes Pod的属性。

1.12：创建deployment

[root@master shuai]# kubectl create -f nginx-delpoy.yaml 
deployment.apps/nginx-deployment created

'//查看刚刚创建的pod资源'
[root@master shuai]# kubectl get pods
NAME                              READY   STATUS    RESTARTS   AGE
nginx-deployment-d55b94fd-f8l85   1/1     Running   0          32s
nginx-deployment-d55b94fd-mbgcm   1/1     Running   0          32s
nginx-deployment-d55b94fd-w9cd6   1/1     Running   0          32s

1.13：查看标签

[root@master shuai]# kubectl get pod --show-labels
NAME                              READY   STATUS    RESTARTS   AGE   LABELS
nginx-deployment-d55b94fd-f8l85   1/1     Running   0          69m   app=nginx,pod-template-hash=d55b94fd
nginx-deployment-d55b94fd-mbgcm   1/1     Running   0          69m   app=nginx,pod-template-hash=d55b94fd
nginx-deployment-d55b94fd-w9cd6   1/1     Running   0          69m   app=nginx,pod-template-hash=d55b94

1.14：通过标签查找pod

[root@master shuai]# kubectl get pod -l app=nginx
NAME                              READY   STATUS    RESTARTS   AGE
nginx-deployment-d55b94fd-f8l85   1/1     Running   0          70m
nginx-deployment-d55b94fd-mbgcm   1/1     Running   0          70m
nginx-deployment-d55b94fd-w9cd6   1/1     Running   0          70m

1.2：创建service提供对外访问的接口

[root@master shuai]# vim nginx-service.yaml

apiVersion: v1  
kind: Service  
metadata:
  name: nginx-service
  labels:
    app: nginx  
spec:
  type: NodePort  
  ports:

  - port: 80
    targetPort: 80  
      selector:
    app: nginx

apiVersion: 指定版本
kind: 类型
name: 指定服务名称
labels: 标签
port: Service 服务暴露的端口
targetPort: 容器暴露的端口
seletor: 关联的Pod的标签  

1.21:创建Service

[root@master shuai]# kubectl create -f nginx-service.yaml 
service/nginx-service created

'查看服务暴露端口【访问pod是有负载均衡的】'
[root@master shuai]# kubectl get svc
NAME            TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)        AGE
kubernetes      ClusterIP   10.0.0.1     <none>        443/TCP        6m57s
nginx-service   NodePort    10.0.0.75    <none>        80:31558/TCP   28s

• 进行访问测试

1.3:详解k8s中的pord

port

port是k8s集群内部访问service的端口，即通过clusterIP: port可以访问到某个service

nodePort

nodePort是外部访问k8s集群中service的端口，通过nodeIP: nodePort可以从外部访问到某个service。

targetPort

targetPort是pod的端口，从port和nodePort来的流量经过kube-proxy流入到后端pod的targetPort上，最后进入容器。

containerPort

containerPort是pod内部容器的端口，targetPort映射到containerPort。

图示：

1.31:生成YAML或者JSON文件

• 测试创建资源对象的命令的正确性【不创建】

[root@master shuai]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run

• 查看生成的yaml文件

'//此命令直接生成yaml文件内容展示出来，并不会保存'
[root@master shuai]# 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: {
    
    }

• 查看生成的json格式

'//此命令直接生成yaml文件内容展示出来，并不会保存'
[root@master shuai]# 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": {
    
    }
}

• 自动将生成的yaml格式的文件另存为

[root@master shuai]# kubectl run nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o yaml > my-deployment.yaml

[root@master shuai]# ls
my-deployment.yaml  nginx-delpoy.yaml  nginx-service.yaml

'//成功生成，可以在此基础上修修改改了'

• 将现有的资源生成模板并导出

[root@master shuai]#  kubectl get pods
NAME                              READY   STATUS    RESTARTS   AGE
nginx-deployment-d55b94fd-f8l85   1/1     Running   0          53m
nginx-deployment-d55b94fd-mbgcm   1/1     Running   0          53m
nginx-deployment-d55b94fd-w9cd6   1/1     Running   0          53m


[root@master shuai]#  kubectl get deploy/nginx-deployment --export -o yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  annotations:
    deployment.kubernetes.io/revision: "1"
  creationTimestamp: null
  generation: 1
  labels:
    app: nginx
  name: nginx-deployment
  selfLink: /apis/extensions/v1beta1/namespaces/default/deployments/nginx-deployment
spec:
  progressDeadlineSeconds: 600
  replicas: 3
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: nginx
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx:1.15.4
        imagePullPolicy: IfNotPresent
        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@master shuai]# kubectl get deploy/nginx-deployment --export -o yaml > shuai.yaml
[root@master shuai]# ls
my-deployment.yaml  nginx-delpoy.yaml  nginx-service.yaml  shuai.yaml

• 查看字段帮助信息

kubectl explain pods.spec.containers

今天就到这把，喜欢可以给博主个关注哦