（转）Kubernetes部署WordPress+MySQL

转：http://www.showerlee.com/archives/2336

这部分我们结合之前的k8s知识点给大家展示如何使用kubernetes部署wordpress+MySQL, 并利用NFS去保存我们容器的源代码以及DB数据.

安装环境

System: CentOS 7.4

Kubernetes: Kubernetes1.9

Docker: 17.03.2-ce

kube-master 10.110.16.10

kube-node-1 10.110.16.11

一. NFS配置:

1. NFS依赖包安装

在Master与Node分别安装NFS组件

# yum install nfs-utils -y

Tip: 这里需保证nfs-utils安装到所有master和node中, 否则容器挂载NFS时会报错.

2. 为Master下mysql data和wordpress源码配置NFS共享目录

# systemctl enable nfs-server && systemctl start nfs-server

# mkdir -p /kube/mysql-db

# mkdir -p /kube/wordpress

# chown nfsnobody:nfsnobody /kube/mysql-db

# chown nfsnobody:nfsnobody /kube/wordpress

# chmod 755 /kube/mysql-db

# chmod 755 /kube/wordpress

# echo -e "/kube/mysql-db    kube-*(rw,sync,no_subtree_check,no_root_squash)" > /etc/exports

# echo -e "/kube/wordpress    kube-*(rw,sync,no_subtree_check,no_root_squash)" >> /etc/exports

Tip: 这里kube-*限制只有kube相关的server才能连接Master下NFS共享目录, no_root_squash参数保证wordpress-mysql pod在初始化mysql配置的时候向在其下挂载的/var/lib/mysql目录有写入权限

3.应用配置

# exportfs -a

二. Persistent volume配置

1.为mysql data与wordpress源码存储创建Persistent volume
# kubectl create -f mysql-pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: mysql-pv
  labels:
    app: mysql
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  nfs:
    path: /kube/mysql-db
    server: kube-master

# kubectl create -f wordpress-pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: wp-pv
  labels:
    app: wordpress
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  nfs:
    path: /kube/wordpress
    server: kube-master

2.创建存放mysql data的PVC

# kubectl create -f mysql-pvc.yaml

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: mysql-pv-claim
  labels:
    app: mysql
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

3.创建存放wordpress源码的PVC
# kubectl create -f wordpress-pvc.yaml

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: wp-pv-claim
  labels:
    app: wordpress
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

查看绑定

# kubectl get pvc

NAME             STATUS    VOLUME     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
mysql-pv-claim   Bound     mysql-pv   5Gi        RWO                           3m
wp-pv-claim      Bound     wp-pv      5Gi        RWO                           6s

三. Secret配置

1.创建mysql root password

# kubectl create secret generic mysql-pass --from-literal='password=countonme'

四. Deployment配置

1.部署mysql deployment with PVC
# kubectl create -f mysql-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: mysql
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: mysql
    spec:
      containers:
      - image: mysql:5.6
        name: mysql
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-pass
              key: password
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-persistent-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-persistent-storage
        persistentVolumeClaim:
          claimName: mysql-pv-claim

2.部署wordpress deployment with PVC

# kubectl create -f wordpress-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: frontend
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: frontend
    spec:
      containers:
      - image: wordpress:4.8-apache
        name: wordpress
        env:
        - name: WORDPRESS_DB_HOST
          value: wordpress-mysql
        - name: WORDPRESS_DB_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-pass
              key: password
        ports:
        - containerPort: 80
          name: wordpress
        volumeMounts:
        - name: wordpress-persistent-storage
          mountPath: /var/www/html
      volumes:
      - name: wordpress-persistent-storage
        persistentVolumeClaim:
          claimName: wp-pv-claim

3.Service配置

Tip: 这里我们开启了node IP的80端口的外部访问权限, 可以方便我们直接利用主机去访问虚拟机任意Node地址从而登录我们的Wordpress网站.

# kubectl create -f wp-svc.yaml

apiVersion: v1
kind: Service
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  ports:
    - port: 3306
  selector:
    app: wordpress
    tier: mysql
  clusterIP: None
---
apiVersion: v1
kind: Service
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  ports:
    - port: 80
      nodePort: 80
  selector:
    app: wordpress
    tier: frontend
  type: NodePort

Tip: 这里service定义的name: wordpress-mysql保证我们wordpress-deployment.yaml定义的如下环境变量可以作为有效的域名成功去访问我们的mysql容器, 保证网站服务器与数据库服务器的通讯.

env:
        - name: WORDPRESS_DB_HOST
          value: wordpress-mysql

五. 验证结果

1.访问wordpress主页

这里我们可以直接在浏览器访问任意node的IP地址从而进入wordpress主页

添加相关信息并初始化安装WordPress

完成安装

后台

主页

2.查看NFS主机对在容器里的mysql data与wordpress root dir的目录挂载.

有兴趣的小伙伴可以直接访问如下代码仓库去下载本文相关代码:

https://git.showerlee.com/showerlee/kube-deploy/tree/master/wordpress-mysql

Finished...

后记:

如果我们使用helm包管理去部署wordpress, 将大大简化我们的工作量.

这里我的代码仓库提供了wordpress chart部署脚本, 以下是详细的部署步骤:

Prerequisite:

Kubernetes cluster setup

http://www.showerlee.com/archives/2200

Helm setup

http://www.showerlee.com/archives/2455

Helm deployment:

# git clone git@git.showerlee.com:showerlee/kube-deploy.git

# cd kube-deploy

# kubectl create secret generic mysql-pass --from-literal='password=countonme'

# helm install --name wordpress-mysql ./wordpress-helm-chart --set service.type=NodePort

NAME:   wordpress-mysql
LAST DEPLOYED: Sat Apr 14 03:09:46 2018
NAMESPACE: default
STATUS: DEPLOYED
 
RESOURCES:
==> v1/PersistentVolume
NAME      CAPACITY  ACCESS MODES  RECLAIM POLICY  STATUS  CLAIM                   STORAGECLASS  REASON  AGE
mysql-pv  5Gi       RWO           Recycle         Bound   default/mysql-pv-claim  1s
wp-pv     5Gi       RWO           Recycle         Bound   default/wp-pv-claim     1s
 
==> v1/PersistentVolumeClaim
NAME            STATUS  VOLUME    CAPACITY  ACCESS MODES  STORAGECLASS  AGE
mysql-pv-claim  Bound   mysql-pv  5Gi       RWO           1s
wp-pv-claim     Bound   wp-pv     5Gi       RWO           1s
 
==> v1/Service
NAME             TYPE       CLUSTER-IP     EXTERNAL-IP  PORT(S)    AGE
wordpress-mysql  ClusterIP  None           <none>       3306/TCP   1s
wordpress        NodePort   10.110.14.233  <none>       80:80/TCP  1s
 
==> v1/Deployment
NAME             AGE
wordpress-mysql  1s
wordpress        1s
 
NOTES:
1. Get the application URL by running these commands:
  export NODE_PORT=$(kubectl get --namespace default -o jsonpath="{.spec.ports[0].nodePort}" services wordpress-mysql-wordpress-helm-chart)
  export NODE_IP=$(kubectl get nodes --namespace default -o jsonpath="{.items[0].status.addresses[0].address}")
  echo http://$NODE_IP:$NODE_PORT