https://kubernetes.io/

https://kubernetes.io/

 

Kubernetes, also known as K8s, is an open-source system for automating deployment, scaling, and management of containerized applications.

It groups containers that make up an application into logical units for easy management and discovery. Kubernetes builds upon 15 years of experience of running production workloads at Google, combined with best-of-breed ideas and practices from the community.

 

 

https://www.pianshen.com/article/8970872160/

 

Kubernetes支持YAML和JSON格式创建资源对象

 

1、JSON格式用于接口之间消息的传递

 

2、YAML格式用于配置和管理

 

YAML是一种简洁的非标记性语言

 

语法格式：

 

  缩进标识层级关系

  不支持制表符缩进，使用空格缩进

  通常开头缩进两个空格

  字符后缩进一个空格，如冒号，逗号等

  “---”表示YAML格式，一个文件的开始

  “#”表示注释

 

查看具体资源的详细信息

 

1、创建pod

 

[root@localhost ~]#  kubectl run nginx --image=nginx:latest --port=80 --replicas=3
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
deployment.apps/nginx created

 

2、查看pod，状态为ContainerCreating

 

[root@localhost ~]# kubectl get pods
NAME                     READY   STATUS              RESTARTS   AGE
nginx-7697996758-j5cwn   0/1     ContainerCreating   0          17s
nginx-7697996758-nw2v4   0/1     ContainerCreating   0          17s
nginx-7697996758-sxkp9   0/1     ContainerCreating   0          17s

 

3、处于动态监听状态

 

[root@localhost ~]# kubectl get pods -w
NAME                     READY   STATUS    RESTARTS   AGE
nginx-7697996758-j5cwn   1/1     Running   0          39s
nginx-7697996758-nw2v4   1/1     Running   0          39s
nginx-7697996758-sxkp9   1/1     Running   0          39s

 

4、再查看，状态为Running

 

[root@localhost ~]# kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-7697996758-j5cwn   1/1     Running   0          79s
nginx-7697996758-nw2v4   1/1     Running   0          79s
nginx-7697996758-sxkp9   1/1     Running   0          79s

 

5、查看镜像资源

 

[root@localhost ~]# kubectl describe pod nginx-7697996758-j5cwn
Name:               nginx-7697996758-j5cwn
Namespace:          default
Priority:           0
PriorityClassName:  <none>
Node:               192.168.35.102/192.168.35.102
Start Time:         Wed, 12 Feb 2020 00:07:58 +0800
Labels:             pod-template-hash=7697996758
                    run=nginx
Annotations:        <none>
Status:             Running
IP:                 172.17.68.2
Controlled By:      ReplicaSet/nginx-7697996758
Containers:
  nginx:
    Container ID:   docker://a55be62040ad1bc1667d48a5b4adab626af857bcbb3f4985591381cf19b1f3ff
    Image:          nginx:latest
    Image ID:       docker-pullable://nginx@sha256:ad5552c786f128e389a0263104ae39f3d3c7895579d45ae716f528185b36bc6f
    Port:           80/TCP
    Host Port:      0/TCP
    State:          Running
      Started:      Wed, 12 Feb 2020 00:08:14 +0800
    Ready:          True
    Restart Count:  0
    Environment:    <none>
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-r5ql5 (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             True 
  ContainersReady   True 
  PodScheduled      True 
Volumes:
  default-token-r5ql5:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-r5ql5

 

6、查看deployment资源

 

[root@localhost ~]# kubectl describe deployment/nginx
Name:                   nginx
Namespace:              default
CreationTimestamp:      Wed, 12 Feb 2020 00:07:57 +0800
Labels:                 run=nginx
Annotations:            deployment.kubernetes.io/revision: 1
Selector:               run=nginx
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:  run=nginx
  Containers:
   nginx:
    Image:        nginx:latest
    Port:         80/TCP
    Host Port:    0/TCP
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Available      True    MinimumReplicasAvailable
  Progressing    True    NewReplicaSetAvailable
OldReplicaSets:  <none>
NewReplicaSet:   nginx-7697996758 (3/3 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  7m1s  deployment-controller  Scaled up replica set nginx-7697996758 to 3

 

用YAML格式创建资源对象

 

1、首先删除之前所创建的资源

 

[root@localhost ~]# kubectl get deployment            查看deployment资源
NAME     DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx    3         3         3            3           3d17h
[root@localhost ~]# kubectl delete deployment/nginx                 #删除镜像资源
deployment.extensions "nginx" deleted
[root@localhost ~]# kubectl get deployment             再次查看deployment资源，确保删除成功
No resources found.

[root@localhost ~]# kubectl get svc            #查看是否有服务运行，有的话删除
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP   7d3h

 

2、查看版本名称

 

[root@localhost ~]# kubectl api-versions
admissionregistration.k8s.io/v1beta1
apiextensions.k8s.io/v1beta1
apiregistration.k8s.io/v1
apiregistration.k8s.io/v1beta1
apps/v1
apps/v1beta1
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
policy/v1beta1
rbac.authorization.k8s.io/v1
rbac.authorization.k8s.io/v1beta1
scheduling.k8s.io/v1beta1
storage.k8s.io/v1
storage.k8s.io/v1beta1
v1

 

3、编写yaml文件进行资源创建

 

[root@localhost ~]# mkdir demo

[root@localhost ~]# cd demo/

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

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.15.4
        ports:
        - containerPort: 80

 

4、查看 kubectl create命令语法

 

[root@localhost demo]# kubectl create --help

Usage:

  kubectl create -f FILENAME [options]

 

 

 

5、创建nginx资源

 

[root@localhost demo]# kubectl create -f nginx-deployment.yaml
deployment.apps/nginx-deployment created

 

6、查看pod资源状态

 

[root@localhost demo]# kubectl get pods
NAME                              READY   STATUS              RESTARTS   AGE
nginx-deployment-d55b94fd-7998c   0/1     ContainerCreating   0          14s
nginx-deployment-d55b94fd-79k65   0/1     ContainerCreating   0          14s
nginx-deployment-d55b94fd-pvjgd   0/1     ContainerCreating   0          14s
[root@localhost demo]# kubectl get pods -w                #处于动态监听状态
NAME                              READY   STATUS              RESTARTS   AGE
nginx-deployment-d55b94fd-7998c   0/1     ContainerCreating   0          29s
nginx-deployment-d55b94fd-79k65   0/1     ContainerCreating   0          29s
nginx-deployment-d55b94fd-pvjgd   0/1     ContainerCreating   0          29s
nginx-deployment-d55b94fd-79k65   1/1     Running             0          36s
nginx-deployment-d55b94fd-pvjgd   1/1   Running   0     40s
nginx-deployment-d55b94fd-7998c   1/1   Running   0     51s
^C[root@localhost demo]# kubectl get pods
NAME                              READY   STATUS    RESTARTS   AGE
nginx-deployment-d55b94fd-7998c   1/1     Running   0          71s
nginx-deployment-d55b94fd-79k65   1/1     Running   0          71s
nginx-deployment-d55b94fd-pvjgd   1/1     Running   0          71s

[root@localhost demo]# kubectl get deploy             #查看资源
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3         3         3            3           7m54s

 

7、编写yaml文件进行资源发布

 

[root@localhost demo]# 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

 

8、发布并查看

 

[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        7d5h
nginx-service   NodePort    10.0.0.134   <none>        80:32509/TCP   5s

 

9、在node节点查看

 

node1：

 

[root@localhost ~]# ipvsadm -L -n

TCP  192.168.35.101:32509 rr
  -> 172.17.45.2:80               Masq    1      0          0         
  -> 172.17.45.4:80               Masq    1      0          0         
  -> 172.17.68.2:80               Masq    1      0          0         

 

node2：

 

[root@localhost ~]# ipvsadm -L -n

TCP  192.168.35.102:32509 rr
  -> 172.17.45.2:80               Masq    1      0          0         
  -> 172.17.45.4:80               Masq    1      0          0         
  -> 172.17.68.2:80               Masq    1      0          0       

 

10、在浏览器上可以进行访问

 

 

 

11、自动测试命令的正确性，并不执行创建

 

[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)

 

12、查看生成yaml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: {}

 

13、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": {}
}

 

14、因为写的语法比较严格，可以把现成的模板重定向保存出来一份，修修改改就可以了。

 

[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               #一些不需要的可以删掉

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

 

15、将现有的资源生成模板导出

 

[root@localhost demo]# kubectl get deploy
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3         3         3            3           160m
[root@localhost demo]# 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: {}

 

15、保存到文件中

 

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

 

16、查看字段帮助信息

 

[root@localhost demo]#  kubectl explain pods.spec.containers