目录

• 资源创建详解
  • 一：Pod及常用参数
    • 1.简介
    • 2.模板
    • 3.删除pod
    • 4.设置Pod主机名
    • 5.镜像拉取策略（ImagePullPolicy）
  • 二：RC
    • 1.简介
    • 2.模板
  • 三：Deployment
    • 1.简介
    • 2.模板
  • 四：HPA
    • 1.简介
    • 2.模板
  • 五：StatefulSet
    • 1.简介
    • 2.模板
  • 六：PV和PVC
  • 八：扩展
    • 8.1.Pod调度到指定的Node

资源创建详解

一：Pod及常用参数

1.简介

2.模板

3.删除pod

示例流程如下：

1. 用户发送删除pod的命令，默认宽限期是30秒；
2. 在Pod超过该宽限期后API server就会更新Pod的状态为“dead”；
3. 在客户端命令行上显示的Pod状态为“terminating”；
4. 跟第三步同时，当kubelet发现pod被标记为“terminating”状态时，开始停止pod进程：
5. 如果在pod中定义了preStop hook，在停止pod前会被调用。如果在宽限期过后，preStop hook依然在运行，第二步会再增加2秒的宽限期；
6. 向Pod中的进程发送TERM信号；
7. 跟第三步同时，该Pod将从该service的端点列表中删除，不再是replication controller的一部分。关闭的慢的pod将继续处理load balancer转发的流量；
8. 过了宽限期后，将向Pod中依然运行的进程发送SIGKILL信号而杀掉进程。
9. Kublete会在API server中完成Pod的的删除，通过将优雅周期设置为0（立即删除）。Pod在API中消失，并且在客户端也不可见。

3.1.默认删除

默认删除，会按照上线的流程，等待宽限期30s

kubectl delete POD --namespace=xxx

3.2.强制删除

设置宽限期为0，会立即删除，没有宽限期

kubectl delete POD --namespace=xxx --force --grace-period=0

4.设置Pod主机名

template.spec.hostname:pod_name 设置pod的主机名

5.镜像拉取策略（ImagePullPolicy）

ImagePullPolicy:

• Always: 不管镜像是否存在，都会拉取
• Never：不管镜像是否存在，都不会拉取
• IfNotPresent：只有当镜像不存在的时候才会进行拉取

注意：

• 默认为IfNotPresent，但:latest标签的镜像默认为Always。
• 拉取镜像时docker会进行校验，如果镜像中的MD5码没有变，则不会拉取镜像数据。
• 生产环境中应该尽量避免使用:latest标签，而开发环境中可以借助:latest标签自动拉取最新的镜像。

二：RC

1.简介

2.模板

官网资料

apiVersion: v1kind: ReplicationController # 定义资源类型metadata: ?name: zabbix-db ?namespace: zabbixspec: ?replicas: 1 ?selector: ???app: zabbix-db ?template: ???metadata: ?????name: zabbix-db ?????labels: ???????app: zabbix-db ???spec: ?????terminationGracePeriodSeconds： 30 # 容器平滑退出时间，默认30s ?????hostname： zabbix-db # 设置容器的主机名 ??????containers: ?????- name: zabbix-db ???????image: mysql:5.7.22 ???????env: ???????- name: MYSQL_DATABASE ?????????value: zabbix ???????- name: MYSQL_USER ?????????value: zabbix ???????- name: MYSQL_PASSWORD ?????????value: zabbix ???????- name: MYSQL_ROOT_PASSWORD ?????????value: Abc123@ ???????ports: ???????- containerPort: 3306 ???????volumeMounts: ???????- mountPath: /var/lib/mysql ?????????readOnly: false ?????????name: zabbix-database ?????volumes: ?????- name: zabbix-database ???????nfs: ?????????server: 172.30.80.222 ?????????path: "/data/zabbix/zabbix_db/mysql"

三：Deployment

1.简介

? Deployment为Pod和Replica Set（升级版的 Replication Controller）提供声明式更新。比于RC，Deployment直接使用kubectl edit deployment/deploymentName 或者kubectl set方法就可以直接升级（原理是Pod的template发生变化，例如更新label、更新镜像版本等操作会触发Deployment的滚动升级）。

2.模板

官方资料

apiVersion: extensions/v1beta1kind: Deploymentmetadata: ?name: nginx ?labels: ???app: nginxspec: ?minReadySeconds: 30 ??# 滚动升级时，容器准备就绪时间最少为30s ?replicas: 5 ?selector: ???matchLabels: ?????app: nginx ?strategy: ???rollingUpdate: ?# 当type为RollingUpdate时，才会进行设置 ?????maxSurge: 25% # 当定义为25%时，容器会先新建百分之25的pod，然后开始滚动升级 ?????maxUnavailable: 25% ??# 每次升级的百分比，也可以是绝对数（5），默认值25% ???type: RollingUpdate # 滚动升级方式，有Recreate：立马关闭所有pod进行升级，RollingUpdate：采用百分比的方式滚动升级 ?template: ????# 模板 ???metadata: ?????creationTimestamp: null ?????labels: ???????app: nginx ???spec: ?????containers: ?????- name: nginx ???????image: nginx:1.7.9 ???????imagePullPolicy: IfNotPresent ???????resources: ?# 资源限制 ?????????requests: ???????????memory: "64Mi" ???????????cpu: "250m" ?????????limits: ???????????memory: "128Mi" ???????????cpu: "500m" ???????env: ???# 设置变量 ???????- name: DB_SERVER_HOST ?????????value: zabbix-db-server ???????- name: MYSQL_DATABASE ?????????value: zabbix ???????- name: MYSQL_USER ?????????value: zabbix ???????- name: MYSQL_PASSWORD ?????????value: zabbix ???????- name: MYSQL_ROOT_PASSWORD ?????????value: Abc123@ ???????- name: ZBX_HISTORYSTORAGEURL ?????????value: http://192.168.2.171:9200 ???????- name: ZBX_HISTORYSTORAGETYPES ?????????value: uint,dbl,str,log,text ???????ports: ???????- containerPort: 80 ??????????livenessProbe: ?#livenessProbe是K8S认为该pod是存活的，不存在则需要kill掉，然后再新启动一个，以达到RS指定的个数。 ?????????httpGet: ???????????path: / ???????????port: 80 ???????????scheme: HTTP ?????????initialDelaySeconds: 30 ?????????timeoutSeconds: 5 ?????????successThreshold: 1 ?????????failureThreshold: 5 ???????readinessProbe: #readinessProbe是K8S认为该pod是启动成功的，这里根据每个应用的特性，自己去判断，可以执行command，也可以进行httpGet。 ?????????httpGet: ???????????path: / ???????????port: 80 ???????????scheme: HTTP ?????????initialDelaySeconds: 30 ?????????timeoutSeconds: 5 ?????????successThreshold: 1 ???????restartPolicy: Always ??# 启动失败时，会重试启动---apiVersion: v1kind: Servicemetadata: ?name: nginx-servicespec: ?type: NodePort ?sessionAffinity: ClientIP ?selector: ???app: nginx ?ports: ???# 将容器的80端口映射到master主机的8888端口 ???- port: 80 ?# pod端口 ?????nodePort: 8888 ???# 宿主机上的端口

四：HPA

1.简介

? Horizontal Pod Autoscaler根据观察到的CPU利用率自动调整复制控制器，部署或副本集中的容器数量（或者，通过 自定义指标 支持，根据其他一些应用程序提供的指标）。请注意，Horizontal Pod Autoscaling不适用于无法缩放的对象，例如DaemonSet。

2.模板

创建一个pod，必须添加资源请求和限制参数

apiVersion: extensions/v1beta1kind: Deploymentmetadata: ?name: nginx ?labels: ???app: nginxspec: ?minReadySeconds: 30 ?replicas: 5 ?selector: ???matchLabels: ?????app: nginx ?strategy: ???rollingUpdate: ?????maxSurge: 25% ?????maxUnavailable: 25% ???type: RollingUpdate ?template: ???metadata: ?????creationTimestamp: null ?????labels: ???????app: nginx ???spec: ?????containers: ?????- name: nginx ???????image: nginx:1.7.9 ???????imagePullPolicy: IfNotPresent ???????resources: ???????????requests: ????# 在使用HPA自动扩展时，必须使用资源请求和资源限制 ???????????memory: "64Mi" ???????????cpu: "250m" ?????????limits: ???????????memory: "128Mi" ???????????cpu: "500m" ???????ports: ???????- containerPort: 80 ?????restartPolicy: Always---apiVersion: v1kind: Servicemetadata: ?name: nginx-servicespec: ?type: NodePort ?sessionAffinity: ClientIP ?selector: ???app: nginx ?ports: ???# 将容器的80端口映射到master主机的8888端口 ???- port: 80 ?????nodePort: 8888

创建HPA

V2 HPA创建规则

官方资料

apiVersion: autoscaling/v1kind: HorizontalPodAutoscaler ??# 指定对象类型metadata: ?name: nginx-hpa ??# 名字 ?labels: ??# 标签 ???app: hpa ???????version: v0.0.1spec: ?scaleTargetRef: ???apiVersion: v1 ???kind: Deployment ???name: nginx # 创建Deployment时，指定的名字 ?minReplicas: 1 ???# 最小pod ?maxReplicas: 10 ??# 最大pod ?targetCPUUtilizationPercentage: 70 ???# CPU用到70%，自动扩展一个pod

查看

# kubectl get hpaNAME ???????REFERENCE ?????????TARGETS ???MINPODS ??MAXPODS ??REPLICAS ??AGEnginx-hpa ??Deployment/nginx ??0% / 70% ??1 ????????10 ???????1 ?????????4d

查看详情

# kubectl describe hpa/nginx-hpaName: ?????????????????????????????????????????????????nginx-hpaNamespace: ????????????????????????????????????????????defaultLabels: ???????????????????????????????????????????????app=hpa ??????????????????????????????????????????????????????version=v0.0.1Annotations: ??????????????????????????????????????????<none>CreationTimestamp: ????????????????????????????????????Thu, 02 Aug 2018 16:39:55 +0800Reference: ????????????????????????????????????????????Deployment/nginxMetrics: ??????????????????????????????????????????????( current / target ) ?resource cpu on pods ?(as a percentage of request): ?0% (0) / 70%Min replicas: ?????????????????????????????????????????1Max replicas: ?????????????????????????????????????????10Conditions: ?Type ???????????Status ?Reason ???????????Message ?---- ???????????------ ?------ ???????????------- ?AbleToScale ????True ???ReadyForNewScale ?the last scale time was sufficiently old as to warrant a new scale ?ScalingActive ??True ???ValidMetricFound ?the HPA was able to succesfully calculate a replica count from cpu resource utilization (percentage of request) ?ScalingLimited ?True ???TooFewReplicas ???the desired replica count was less than the minimum replica countEvents: ??????????<none>

五：StatefulSet

1.简介

2.模板

2.1.基础环境介绍

apiVersion: v1kind: Servicemetadata: ?name: zoo01 ?labels: ???app: zoo01spec: ?ports: ?- port: 2888 ???name: leader-listen ?- port: 3888 ???name: leader-vote ?clusterIP: None ?selector: ???app: zoo01---apiVersion: apps/v1beta1kind: StatefulSetmetadata: ?name: zoo01 ?labels: ???app: zoo01spec: ?serviceName: "zoo01-service" ?replicas: 1 ?template: ???metadata: ?????creationTimestamp: null ?????labels: ???????app: zoo01 ???spec: ?????terminationGracePeriodSeconds: 30 ?????hostname: zoo01 ?????containers: ?????- name: zoo01 ???????image: zookeeper:3.5 ???????imagePullPolicy: IfNotPresent ???????resources: ?????????requests: ???????????memory: "64Mi" ???????????cpu: "250m" ?????????limits: ???????????memory: "128Mi" ???????????cpu: "500m" ???????env: ?????????- name: ZOO_MY_ID ???????????value: "1" ?????????- name: ZOO_SERVERS ???????????value: "server.1=zoo01:2888:3888 server.2=zoo02:2888:3888 server.3=zoo03:2888:3888" ???????ports: ?????????- containerPort: 2181 ?????????- containerPort: 2888 ?????????- containerPort: 3888 ?????restartPolicy: Always

六：PV和PVC

PV

apiVersion: v1kind: PersistentVolumemetadata: ?name: gitlab-pv ?namespace: devspec: ?capacity: ???storage: 10Gi ??# 大小 ?accessModes: ???- ReadWriteOnce # 读写模式 ?persistentVolumeReclaimPolicy: Recycle ?storageClassName: slow ?mountOptions: # 挂载选项 ???- hard ???- nfsvers=4.1 ?nfs: ?# nfs服务器地址 ???path: /data/gitlab ???server: 172.30.80.222

PVC

kind: PersistentVolumeClaimapiVersion: v1metadata: ?name: gitlab-pvc ?namespace: dev ?labels: ???type: nfsspec: ?accessModes: ???- ReadWriteOnce # PV和PVC的绑定关系，主要依靠读写模式和存储大小 ?storageClassName: slow ?resources: ???requests: ?????storage: 10Gi ???selector: ???matchLabels: ?????name: gitlab-pv

Pod

八：扩展

8.1.Pod调度到指定的Node

介绍：

? Pod.spec.nodeSelector通过kubernetes的label-selector机制选择节点，由调度器调度策略匹配label，而后调度Pod到目标节点，该匹配规则属于强制约束。

apiVersion: extensions/v1beta1kind: Deploymentmetadata: ?name: zabbix-server ?namespace: zabbixspec: ?replicas: 1 ?selector: ???matchLabels: ?????app: zabbix-server ?template: ???metadata: ?????name: zabbix-server ?????labels: ???????app: zabbix-server ???spec: ?????nodeSelector: # 基于node的lable进行调度 ???????kubernetes.io/hostname: 172.30.80.220 ??# 指定主机的lable标签 ?????containers: ?????- name: zabbix-server ???????image: zabbix/zabbix-server-mysql:latest ???????env: ???????- name: DB_SERVER_HOST ?????????value: zabbix-db-server ???????- name: MYSQL_DATABASE ?????????value: zabbix ???????- name: MYSQL_USER ?????????value: zabbix ???????- name: MYSQL_PASSWORD ?????????value: zabbix ???????- name: MYSQL_ROOT_PASSWORD ?????????value: Abc123@ ???????- name: ZBX_HISTORYSTORAGEURL ?????????value: http://192.168.2.171:9200 ???????- name: ZBX_HISTORYSTORAGETYPES ?????????value: uint,dbl,str,log,text ???????ports: ???????- containerPort: 10051

kubernetes资源创建详解【持续完善中】

原文地址：https://www.cnblogs.com/GXLo/p/9983716.html