一、StorageClass存储类理论
StorageClass的作用主要有以下几个方面：
动态存储卷分配：StorageClass可以根据定义的属性动态地创建存储卷，无需手动创建和管理存储卷。
存储卷的属性管理：StorageClass可以定义存储卷的属性，如存储类型、存储容量、访问模式等，从而更好地满足应用程序的存储需求。
存储资源的管理：StorageClass可以将存储资源进行分类管理，方便开发者根据应用程序的需求进行选择。
每个 StorageClass 都有一个供应商（Provisioner），用来决定使用哪个卷插件制备 PV。 该字段必须指定，官网提供供应商如下表：
本文章以NFS为例，要想使用NFS，我们需要一个nfs-client的自动装载程序，称之为provisioner，这个程序会使用我们已经配置好的NFS服务器自动创建持久卷，也就是自动帮我们创建PV。
二、案例：Storageclass存储类实战演示
1、搭建NFS服务端
注意：K8S集群所有Node节点都需要安装 nfs-utils 包
yum -y install nfs-utilsmkdir /data/nfs_pro -pvim /etc/exports/data/test *(rw,sync,no_root_squash)
加载生效 && 启动NFS服务
exportfs -arvsystemctl enable nfs --now
2、搭建NFS供应商(provisioner)
第一步：创建运行nfs-provisioner需要使用的SA账号
[root@Master testv2]# more 00-nfs-provisioner.yaml ---apiVersion: v1kind: ServiceAccountmetadata: name: nfs-nginx
执行 YAML 文件 && 查看创建的 SA 账号：
kubectl apply -f 00-nfs-provisioner.yamlkubectl get sa nfs-nginx
kubectl get sa nfs-nginxNAME SECRETS AGEnfs-nginx 1 18h
第二步：针对SA账号进行授权：
kubectl create clusterrolebinding nfs-nginx --clusterrole=cluster-admin --serviceaccount=default:nfs-nginx
第三步：安装01-nfs-deployment.yaml程序 YAML 如下：
cat 01-nfs-deployment.yaml ---kind: DeploymentapiVersion: apps/v1metadata: name: nfs-nginxspec: selector: matchLabels: app: nfs-nginx replicas: 3 strategy: # 更新策略 type: Recreate template: metadata: labels: app: nfs-nginx spec: serviceAccount: nfs-nginx # 指定SA账号 containers: - name: nfs-nginx image: registry.cn-beijing.aliyuncs.com/mydlq/nfs-subdir-external-provisioner:v4.0.0 imagePullPolicy: IfNotPresent volumeMounts: - name: nfs-client-root mountPath: /persistentvolumes env: - name: PROVISIONER_NAME value: example.com/nfs-nginx # NFS供应商名称 - name: NFS_SERVER value: 172.16.42.5 # NFS服务端地址 - name: NFS_PATH value: /data/test/ # NFS共享目录 volumes: - name: nfs-client-root nfs: server: 172.16.42.5 # NFS服务端地址 path: /data/test/ # NFS共享目录
执行YAML 文件 && 查看 Pod状态：
kubectl apply -f 01-nfs-deployment.yaml deployment.apps/nfs-nginx unchanged
kubectl get pods NAME READY STATUS RESTARTS AGEnfs-nginx-97f96446d-6ng62 1/1 Running 0 3snfs-nginx-97f96446d-9kf6x 1/1 Running 0 3snfs-nginx-97f96446d-cbbz9 1/1 Running 0 3s
3、创建StorageClass存储类
cat 02-nfs-storageclass.yaml ---kind: StorageClassapiVersion: storage.k8s.io/v1metadata: name: nfs-nginxprovisioner: example.com/nfs-nginx # 指定NFS供应商名称,和上面对应上
注意：provisioner处写的example.com/nfs应该跟安装01-nfs-deployment.yaml时候的env下的PROVISIONER_NAME的value值保持一致。
执行YAML文件 && 查看storageclass 状态：
kubectl apply -f 02-nfs-storageclass.yaml kubectl get sc nfs-nginx
kubectl get sc nfs-nginxNAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGEnfs-nginx example.com/nfs-nginx Delete Immediate false 18h
4、创建PVC，通过StorageClass动态生成PV
cat 03-nfs-pvc.yaml ---kind: PersistentVolumeClaimapiVersion: v1metadata: name: nfs-nginxspec: accessModes: ["ReadWriteMany"] resources: requests: storage: 6Gi storageClassName: nfs-nginx # 指定使用storageclass的名称,来自动生产PV
执行YAML 文件 && 查看是否自动生成PV
kubectl apply -f 03-nfs-pvc.yamlkubectl get pvc
[root@Master testv2]# kubectl apply -f 03-nfs-pvc.yaml persistentvolumeclaim/nfs-nginx unchanged[root@Master testv2]# kubectl get pvc nfs-nginxNAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGEnfs-nginx Bound pvc-770e8d47-5cbf-4115-87ea-bbcc8551b993 6Gi RWX nfs-nginx 18h
如上图已经自动创建PV，并绑定上PVC了
5、创建Pod挂载PVC
cat 04-nfs-pod-demo.yaml ---apiVersion: v1kind: Podmetadata: name: nfs-nginx labels: type: nfs-v1spec: volumes: - persistentVolumeClaim: claimName: nfs-nginx # 指定PVC name: nfs-nginx # 卷名称 containers: - name: nfs-nginx-demo image: nginx:latest imagePullPolicy: IfNotPresent volumeMounts: - name: nfs-nginx # 指定上面卷名称 mountPath: /usr/share/nginx/html # 容器挂载目录
执行 YAML 文件 && 查看Pod状态：
kubectl apply -f 04-nfs-pod-demo.yamlubectl get pods nfs-nginx -o wide --show-labels
[root@Master testv2]# kubectl apply -f 04-nfs-pod-demo.yaml pod/nfs-nginx configured[root@Master testv2]# kubectl get pods nfs-nginx -o wide --show-labelsNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELSnfs-nginx 1/1 Running 0 18h 10.244.1.99 node1 type=nfs-v1
在 PVC 绑定宿主机目录，创建 index.html 文件
echo "storageclass demo successd...." > /data/test/default-storageclass-pvc-demo-pvc-6b213e25-12a2-4ffd-a1ff-af23ec531233/index.html
获取Pod IP访问网站：
kubectl get pods nfs-nginx -o wide
[root@Master testv2]# kubectl get pods nfs-nginx -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnfs-nginx 1/1 Running 0 18h 10.244.1.99 node1 [root@Master testv2]# curl 10.244.1.99storageclass demo successd....
三、步骤总结
1、搭建NFS服务端
2、搭建NFS供应商，指定NFS服务端IP地址及共享目录
3、创建StorageClass资源，指定使用NFS供应商
4、创建PVC，使用storageClassName 自动指定使用StorageClass
5、创建Pod，使用PVC
————————————————————————————-
Dockerfile 镜像构建
1、准备 tomcat jdk 包
apache-tomcat-10.1.16.tar.gz dockerfile jdk-11.0.21_linux-x64_bin.tar.gz
# Centos7 image# VERSION 2# Author: sixmillions# 指定基于的容器镜像FROM centos:7# 维护者信息MAINTAINER sixmillions# 镜像的操作指令# 设置时间RUN /bin/cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime \ && echo 'Asia/Shanghai' >/etc/timezone# 指定jdk1.8add jdk-11.0.21_linux-x64_bin.tar.gz /usr/local/add apache-tomcat-10.1.16.tar.gz /usr/local/# RUN rm -f /usr/local/apache-tomcat-8.5.34/webapps/ROOT/favicon.icoRUN mkdir -p /data && mv /usr/local/apache-tomcat-10.1.16 /usr/local/tomcatenv JAVA_HOME=/usr/local/jdk-11.0.21env PATH=${JAVA_HOME}/bin:$PATHenv LC_ALL=en_US.UTF-8# 一会我们做pv存储,直接将webapps目录映射出来.# ADD helloworld.war /usr/local/apache-tomcat-8.5.34/webapps/# RUN chmod +x /usr/local/apache-tomcat-7.0.68/bin/*expose 8080# 容器启动时执行指令ENTRYPOINT [ "/usr/local/tomcat/bin/catalina.sh", "run" ]
打包基础镜像
docker build -t helloworldtomcat8 .
[root@Master dockerfile]# docker images hellowoldtomcat8REPOSITORY TAG IMAGE ID CREATED SIZEhellowoldtomcat8 latest e13125a33897 18 hours ago 520MB
3. 上传到私有仓库
将打包好的镜像上传到私有仓库,方便其他节点获取
master节点
# 改个名字docker tag hellowoldtomcat8 101.43.xxx.xxx:8888/test/helloworldtomcat8:latest# 上传docker push 101.43.196.155:8888/test/helloworldtomcat8
node节点
下载镜像
docker pull 101.43.196.155:8888/test/helloworldtomcat8
四、使用StorageClass 创建 tomcat logs webapp 存储
1、创建tomcat-logs-pvc
cat 03-nfs-tomcat-logs-pvc.yaml ---kind: PersistentVolumeClaimapiVersion: v1metadata: name: nfs-tomcat-logsspec: accessModes: ["ReadWriteMany"] resources: requests: storage: 7Gi storageClassName: nfs-nginx # 指定使用storageclass的名称,来自动生产PV
查看tomcat-logs-pvc 创建
kubectl get pvc nfs-tomcat-logsNAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGEnfs-tomcat-logs Bound pvc-618a8eaf-e798-4b03-b2c6-9b146eb6d792 7Gi RWX nfs-nginx 17h
1、创建 tomcat-webapp-pvc
cat 03-nfs-tomcat-webapp-pvc.yaml ---kind: PersistentVolumeClaimapiVersion: v1metadata: name: nfs-tomcat-webappspec: accessModes: ["ReadWriteMany"] resources: requests: storage: 7Gi storageClassName: nfs-nginx # 指定使用storageclass的名称,来自动生产PV
查看tomcat-webapp pvc 创建
[root@Master tomcat]# kubectl apply -f 03-nfs-tomcat-webapp-pvc.yaml persistentvolumeclaim/nfs-tomcat-webapp unchanged[root@Master tomcat]# kubectl get pvc nfs-tomcat-webappNAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGEnfs-tomcat-webapp Bound pvc-0b0f9b13-1bf0-46ff-8ce5-a95ec8a6dedd 7Gi RWX nfs-nginx 17h
创建 tomcat demo
cat 04-nfs-pod-demo.yaml apiVersion: apps/v1kind: DaemonSetmetadata: name: tomcattestspec: selector: matchLabels: app: tomcattest template: metadata: labels: app: tomcattest spec: containers: - name: tomcattest image: 101.43.196.155:8888/test/helloworldtomcat8 imagePullPolicy: Always ports: - containerPort: 8080 volumeMounts: - name: logs mountPath: /usr/local/tomcat/logs - name: webapps mountPath: /usr/local/tomcat/webapps volumes: - name: logs persistentVolumeClaim: claimName: nfs-tomcat-logs - name: webapps persistentVolumeClaim: claimName: nfs-tomcat-webapp
查看创建结果
[root@Master tomcat]# kubectl apply -f 05-nfs-pod-demo.yaml daemonset.apps/tomcattest unchanged[root@Master tomcat]# kubectl get pods NAME READY STATUS RESTARTS AGEtomcattest-8rcbl 1/1 Running 0 17htomcattest-9mv7p 1/1 Running 0 17htomcattest-qwgmm 1/1 Running 0 17h
2.构建service编写yaml文件
cat 06-tomcat-svc.yaml apiVersion: v1kind: Servicemetadata: name: tomcattest-servicespec: type: NodePort ports: - port: 8080 name: tomcat targetPort: 8080 nodePort: 32012 protocol: TCP selector: app: tomcattest
构建Service
kubectl apply -f 06-tomcat-svc.yaml service/tomcattest-service unchanged
[root@Master tomcat]# ifconfig eth0eth0: flags=4163 mtu 1500 inet 172.16.42.3 netmask 255.255.255.0 broadcast 172.16.42.255 inet6 fe80::216:3eff:fe08:a149 prefixlen 64 scopeid 0x20 ether 00:16:3e:08:a1:49 txqueuelen 1000 (Ethernet) RX packets 26297104 bytes 8933567314 (8.3 GiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 20506729 bytes 14593454145 (13.5 GiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0[root@Master tomcat]# curl 172.16.42.3:32012<html lang="en">HTTP Status <span>404</span> – Not Found <style type="text/css">body {font-family:Tahoma,Arial,sans-serif;} h1, h2, h3, b {color:white;background-color:#525D76;} h1 {font-size:22px;} h2 {font-size:16px;} h3 {font-size:14px;} p {font-size:12px;} a {color:black;} .line {height:1px;background-color:#525D76;border:none;}HTTP Status 404 – Not Found
<hr class="line" />Type Status Report
Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.
<hr class="line" />Apache Tomcat/10.1.16
[root@Master tomcat]#
测试增加一个界面在映射文件
root@Node2 helloworld]# pwd/data/test/default-nfs-tomcat-webapp-pvc-0b0f9b13-1bf0-46ff-8ce5-a95ec8a6dedd/helloworld[root@Node2 helloworld]# cat index.html k8s-homework-successful!
[root@Master tomcat]# curl 172.16.42.3:32012/helloworld/index.htmlk8s-homework-successful!