k8s单机部署wordpress

在前文k8s部署有状态应用中,简单介绍了StatefulSet的使用。

  • 《Kubectl 部署有状态应用(上)》
  • 《Kubectl 部署有状态应用(下)》

本教程将展示如何使用 Minikube 部署 WordPress 站点和 MySQL 数据库。这两个应用程序都使用 PersistentVolumes 和 PersistentVolumeClaims 来存储数据。

PersistentVolume (PV) 是集群中的一块存储,由管理员手动配置,或者由 Kubernetes 使用 StorageClass动态配置。PersistentVolumeClaim (PVC )是用户提出的存储请求,可以通过 PV 来满足。PersistentVolumes 和 PersistentVolumeClaims 独立于 Pod 生命周期,并通过重新启动、重新调度甚至删除 Pod 来保留数据。

本文目标

  • 创建pv和pvc
  • 创建一个包含Secret generator 和mysql与wordpress配置的yaml文件
  • 部署
  • 清除

创建kustomization

Secret是存储密码或密钥等敏感数据的对象。从 1.14 开始,kubectl支持使用 kustomization 文件管理 Kubernetes 对象。

执行以下命令将Secret添加到kustomization.yaml。记得更换password

cat <<EOF >./kustomization.yaml
secretGenerator:
- name: mysql-passliterals:- password=YOUR_PASSWORD
EOF

创建MySQL yaml

vim mysql-deployment.yaml

MySQL 容器将 PersistentVolume 挂载在 /var/lib/mysql 处。环境MYSQL_ROOT_PASSWORD 变量设置来自 Secret 的数据库密码。

apiVersion: v1
kind: Service
metadata:name: wordpress-mysqllabels:app: wordpress
spec:ports:- port: 3306selector:app: wordpresstier: mysqlclusterIP: None
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:name: mysql-pv-claimlabels:app: wordpress
spec:accessModes:- ReadWriteOnceresources:requests:storage: 20Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:name: wordpress-mysqllabels:app: wordpress
spec:selector:matchLabels:app: wordpresstier: mysqlstrategy:type: Recreatetemplate:metadata:labels:app: wordpresstier: mysqlspec:containers:- image: mysql:8.0name: mysqlenv:- name: MYSQL_ROOT_PASSWORDvalueFrom:secretKeyRef:name: mysql-passkey: password- name: MYSQL_DATABASEvalue: wordpress- name: MYSQL_USERvalue: wordpress- name: MYSQL_PASSWORDvalueFrom:secretKeyRef:name: mysql-passkey: passwordports:- containerPort: 3306name: mysqlvolumeMounts:- name: mysql-persistent-storagemountPath: /var/lib/mysqlvolumes:- name: mysql-persistent-storagepersistentVolumeClaim:claimName: mysql-pv-claim

创建Wordpress yaml

vim wordpress-deployment.yaml

wordpress-deployment.yaml描述了单实例 WordPress 容器将PersistentVolume挂载在/var/www/html 作为网站数据文件 。WORDPRESS_DB_HOST环境变量设置是上面定义的MySQL Service的名称。WORDPRESS_DB_PASSWORD 环境变量在kustomization中设置。

apiVersion: v1
kind: Service
metadata:name: wordpresslabels:app: wordpress
spec:ports:- port: 80selector:app: wordpresstier: frontendtype: LoadBalancer
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:name: wp-pv-claimlabels:app: wordpress
spec:accessModes:- ReadWriteOnceresources:requests:storage: 20Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:name: wordpresslabels:app: wordpress
spec:selector:matchLabels:app: wordpresstier: frontendstrategy:type: Recreatetemplate:metadata:labels:app: wordpresstier: frontendspec:containers:- image: wordpress:6.2.1-apachename: wordpressenv:- name: WORDPRESS_DB_HOSTvalue: wordpress-mysql- name: WORDPRESS_DB_PASSWORDvalueFrom:secretKeyRef:name: mysql-passkey: password- name: WORDPRESS_DB_USERvalue: wordpressports:- containerPort: 80name: wordpressvolumeMounts:- name: wordpress-persistent-storagemountPath: /var/www/htmlvolumes:- name: wordpress-persistent-storagepersistentVolumeClaim:claimName: wp-pv-claim

mysql 和wordpress的配置文件也可以从网上下载下来。

curl -LO https://k8s.io/examples/application/wordpress/mysql-deployment.yaml
curl -LO https://k8s.io/examples/application/wordpress/wordpress-deployment.yaml

将配置文件添加到kustomization.yaml文件中。

secretGenerator:
- name: mysql-passliterals:- password=123456
resources:- mysql-deployment.yaml- wordpress-deployment.yaml

一键部署

kubectl apply -k ./

有以下输出:

secret/mysql-pass-kkcc2b926b created
service/wordpress created
service/wordpress-mysql created
persistentvolumeclaim/mysql-pv-claim created
persistentvolumeclaim/wp-pv-claim created
deployment.apps/wordpress created
deployment.apps/wordpress-mysql created
验证 Secret 是否存在
kubectl get secrets
------
NAME                    TYPE     DATA   AGE
mysql-pass-kkcc2b926b   Opaque   1      26s
验证 PersistentVolume 是否已动态配置
kubectl get pvc
------
NAME             STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
mysql-pv-claim   Bound    pvc-2675097d-aec0-4f96-9e80-047588bcfd9a   20Gi       RWO            standard       94s
wp-pv-claim      Bound    pvc-d5d19a5c-d9c2-41d7-8de8-f7a1bec03fc1   20Gi       RWO            standard       94s
验证 Pod 是否正在运行
kubectl get pods
------
NAME                               READY   STATUS    RESTARTS   AGE
wordpress-65dcc8b9cd-bz875         1/1     Running   0          2m5s
wordpress-mysql-7646676cfc-98pxd   1/1     Running   0          2m5s
验证服务是否正在运行
kubectl get services wordpress
------
NAME        TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
wordpress   LoadBalancer   10.110.228.240   <pending>     80:30692/TCP   3m2s

获取 WordPress 服务的 IP 地址

minikube service wordpress --url
------
http://127.0.0.1:52551
❗  因为你正在使用 darwin 上的 Docker 驱动程序,所以需要打开终端才能运行它。

复制 IP 地址,然后在浏览器中加载页面以访问wordpress站点。

清除

清理所有服务执行kubectl delete -k ./即可。

kubectl delete -k ./
------
secret "mysql-pass-kkcc2b926b" deleted
service "wordpress" deleted
service "wordpress-mysql" deleted
persistentvolumeclaim "mysql-pv-claim" deleted
persistentvolumeclaim "wp-pv-claim" deleted
deployment.apps "wordpress" deleted
deployment.apps "wordpress-mysql" deleted