一、资源清单概念

• 资源/对象的类型
  • 工作负载型资源：Pod, ReplicaSet, Deployment, StatefulSet, DaemonSet, Job, Cronjob, ...
  • 服务发现及均衡性资源：Service, Ingress, ...
  • 配置与存储型资源：Volume, CSI, ConfigMap, DownwardAPI
  • 集群级资源：Namespace, Node, Role, ClusterRole, RoleBinding, ClusterRoleBinding
  • 元数据型资源：HPA, PodTemplate, LimitRange

二、配置清单入门

1、配置清单简介

• 输出配置清单

~]# kubectl get pod nginx-deploy-bc9ff65dd-m8k46 -o yaml

apiVersion: v1  #对象属于哪个组，此对象属于核心组，core/v1

kind: Pod  #具体资源对象

metadata:  #元数据

  creationTimestamp: "2019-06-24T13:33:09Z"

  generateName: nginx-deploy-bc9ff65dd-

  labels:

    pod-template-hash: bc9ff65dd

    run: nginx-deploy

  name: nginx-deploy-bc9ff65dd-m8k46

  namespace: default

  ownerReferences:

  - apiVersion: apps/v1

    blockOwnerDeletion: true

    controller: true

    kind: ReplicaSet

    name: nginx-deploy-bc9ff65dd

    uid: 0e2bf48a-822f-4a05-8779-fa97998f0eb3

  resourceVersion: "86123"

  selfLink: /api/v1/namespaces/default/pods/nginx-deploy-bc9ff65dd-m8k46

  uid: 817f0411-67c6-43db-aef0-54ac0465bc94

spec:  #规格，定义资源对象的特性或规范，也叫期望状态

  containers:

  - image: nginx:1.14

    imagePullPolicy: IfNotPresent

    name: nginx-deploy

    ports:

    - containerPort: 80

      protocol: TCP

    resources: {}

    terminationMessagePath: /dev/termination-log

    terminationMessagePolicy: File

    volumeMounts:

    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount

      name: default-token-4q4c9

      readOnly: true

  dnsPolicy: ClusterFirst

  enableServiceLinks: true

  nodeName: node01

  priority: 0

  restartPolicy: Always

  schedulerName: default-scheduler

  securityContext: {}

  serviceAccount: default

  serviceAccountName: default

  terminationGracePeriodSeconds: 30

  tolerations:  #容忍度

  - effect: NoExecute

    key: node.kubernetes.io/not-ready

    operator: Exists

    tolerationSeconds: 300

  - effect: NoExecute

    key: node.kubernetes.io/unreachable

    operator: Exists

    tolerationSeconds: 300

  volumes:

  - name: default-token-4q4c9

    secret:

      defaultMode: 420

      secretName: default-token-4q4c9

status:  #显示资源当前状态，当前状态无限向期望状态靠近

  conditions:

  - lastProbeTime: null

    lastTransitionTime: "2019-06-24T13:33:09Z"

    status: "True"

    type: Initialized

  - lastProbeTime: null

    lastTransitionTime: "2019-06-24T13:40:27Z"

    status: "True"

    type: Ready

  - lastProbeTime: null

    lastTransitionTime: "2019-06-24T13:40:27Z"

    status: "True"

    type: ContainersReady

  - lastProbeTime: null

    lastTransitionTime: "2019-06-24T13:33:09Z"

    status: "True"

    type: PodScheduled

  containerStatuses:

  - containerID: docker://fa614bd334c9985121436b1ef3bf3c2cab6ca77e8e2a8171ad37172872f6147b

    image: nginx:1.14

    imageID: docker-pullable://nginx@sha256:f7988fb6c02e0ce69257d9bd9cf37ae20a60f1df7563c3a2a6abe24160306b8d

    lastState: {}

    name: nginx-deploy

    ready: true

    restartCount: 0

    state:

      running:

        startedAt: "2019-06-24T13:40:26Z"

  hostIP: 192.168.100.61

  phase: Running

  podIP: 10.244.1.2

  qosClass: BestEffort

  startTime: "2019-06-24T13:33:09Z"

• 创建资源的方法
  • apiserver仅接受json格式的资源定义
  • yaml格式提供配置清单，apiserver可自动将其转为json格式再提交
• 资源引用方式

/api/GROUP/VERSION/namespaces/NAMESPACE/TYPE/NAME

• 资源定义帮助获取

~]# kubectl explain pods

2、配置清单的常用字段定义

• apiVersion：group/version

~]# kubectl api-versions  #显示所有支持的api版本

• kind：资源类别，Pod, Service, ...
• metadata：元数据

name：资源名称

namespace：kubernetes级别的名称空间

labels：标签

annotaions：注解

• spec：期望状态，disired state
• status：当前状态，current state，此字段有kubernetes集群自动维护，无需定义

三、Pod资源配置清单定义

1. 创建一个自主式Pod

apiVersion: v1

kind: Pod

metadata:

  name: pod-demo

  namespace: default

  labels:

    app: myapp

    tier: frontend  #层次：前端

spec:

  containers:

  - name: myapp

    image: dongfeimg/myapp:v1

1. 根据配置清单启动/删除pod

# kubectl create -f pod-demo.yaml

# kubectl describe pods pod-demo  #查看详细信息

# kubectl delete -f pod-demo.yaml