於kubernets (k8s) 裝 wordpress

於kubernets (k8s) 裝 wordpress，並將資料庫及相關檔案持久化(放實體路徑)，
以下為執行的步驟

1.設定DB的環境變數

1) vi mydb_env

MYSQL_ROOT_PASSWORD=Redhat1!
TZ="Asia/Taipei"

2) 設定configmaps

kubectl create cm mydb-env –from-env-file=mydb_env

3) 查看configmaps設定結果

kubectl describe cm mydb-env

2.設定DB密碼-secret

1) 設定secret

kubectl create secret generic mydb-pwd –from-literal=MYSQL_ROOT_PASSWORD=Redhat1!

2) 查看secret

kubectl describe secret mydb-pwd

3.建mydb deployment未指定DB密碼，故啟動失敗

kubectl create deployment mydb --image=mariadb --port 3306

4.設定環境變數

1) 將deployment mydb設定檔存成檔案

kubectl get deployments mydb -o yaml > deployment_mydb.yaml

2) 設定環境變數

vi deployment_mydb.yaml

      containers:
      - image: mariadb
        imagePullPolicy: Always
        name: mariadb
        ports:
        - containerPort: 3306
          protocol: TCP
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              key: MYSQL_ROOT_PASSWORD
              name: mydb-pwd
        - name: TZ
          valueFrom:
            configMapKeyRef:
              key: TZ
              name: mydb-env

3) 重建deployment

kubectl delete deployment mydb
kubectl apply -f deployment_mydb.yaml

註: 可直接由 kubectl edit deployments mydb 做編輯

5.將資料庫放在host server

1) 於host server建 /data/db (mkdir /data/db)

2) 設定hostPath: /data/db

vi deployment_mydb.yaml

      containers:
      - args:
        - --character-set-server=utf8mb4
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              key: MYSQL_ROOT_PASSWORD
              name: mydb-pwd
        - name: TZ
          valueFrom:
            configMapKeyRef:
              key: TZ
              name: mydb-env
        image: mariadb
        imagePullPolicy: Always
        name: mariadb
        ports:
        - containerPort: 3306
          protocol: TCP
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
          - mountPath: /var/lib/mysql
            name: mydb-data
      volumes:
      - name: mydb-data
        hostPath:
          path: /data/db
          type: Directory

4) 重建deployment

kubectl delete deployment mydb
kubectl apply -f deployment_mydb.yaml

6.進入pod內操作並建立database wp

kubectl exec -it pod/mydb-5b9dbbbf54-6k8wl — bash
create database wp;

7.設定mydb service (不一定要做此項)

1) kubectl expose deployment mydb –port=3306
2) kubectl get svc => 預設為ClusterIP
3) kubectl edit svc mydb => 將type由ClusterIP改為NodePort

8.設定wordpress環境變數

1) vi wordpress_env

WORDPRESS_DB_NAME=wp
WORDPRESS_DB_USER=root
WORDPRESS_DB_HOST=mydb
WORDPRESS_DB_PASSWORD=Redhat1!
ServerName=localhost

2) 設定configmaps

kubectl create cm wordpress-env –from-env-file=wordpress_env

kubectl get cm wordpress-env
kubectl describe configmaps wordpress-env

9.建立wordpress application

1) 建myweb deployment

kubectl create deployment myweb --image=wordpress

2) 設定環境變數

      containers:
      - image: wordpress
        imagePullPolicy: Always
        name: wordpress
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        env:
        - name: WORDPRESS_DB_NAME
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_NAME
              name: wordpress-env
        - name: WORDPRESS_DB_USER
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_USER
              name: wordpress-env
        - name: WORDPRESS_DB_PASSWORD
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_PASSWORD
              name: wordpress-env
        - name: ServerName
          valueFrom:
            configMapKeyRef:
              key: ServerName
              name: wordpress-env
        - name: WORDPRESS_DB_HOST
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_HOST
              name: wordpress-env

10.將檔案建在host server

1) 於host server建 /data/wordpress (mkdir /data/wordpress)

2) 設定hostPath: /data/wordpress
kubectl edit deployment myweb

      containers:
      - env:
        - name: WORDPRESS_DB_NAME
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_NAME
              name: wordpress-env
        - name: WORDPRESS_DB_USER
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_USER
              name: wordpress-env
        - name: WORDPRESS_DB_PASSWORD
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_PASSWORD
              name: wordpress-env
        - name: ServerName
          valueFrom:
            configMapKeyRef:
              key: ServerName
              name: wordpress-env
        - name: WORDPRESS_DB_HOST
          valueFrom:
            configMapKeyRef:
              key: WORDPRESS_DB_HOST
              name: wordpress-env
        image: wordpress
        imagePullPolicy: Always
        name: wordpress
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
        - mountPath: /var/www/html
          name: myweb-data
      volumes:
      - name: myweb-data
        hostPath:
          path: /data/wordpress
          type: Directory