Kubernetes集群中WordPress启动失败：无法打开流（文件或目录不存在）

在Kubernetes集群部署WordPress时启动失败，报错信息为failed to open stream: No such file or directory，已为Pod的/var/www/html路径挂载存储卷。

错误日志 #

No 'wp-config.php' found in /var/www/html, but 'WORDPRESS_...' variables supplied; copying '/usr/src/wordpress/wp-config-
[php:error] [pid 56] [client 10.244.2.0:44079] PHP Fatal error:  
Uncaught Error: Failed opening required '/var/www/html/wp-load.php' (include_path='.:/usr/local/lib/php') in /var/www/html/wp-blog-header.php:13\nStack trace:\n#0 /var/www/html/index.php(17): require()\n#1 {main}\n  
thrown in /var/www/html/wp-blog-header.php on line 13, 
referer: http://localhost:8001/

NFS目录情况 #

NFS挂载的目录为空，未包含任何WordPress核心文件。

使用的Kubernetes配置文件 #

---
# Wordpress deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress
spec:
  replicas: 1
  selector:
    matchLabels:
      app: wordpress-app
  template:
    metadata:
      labels:
        app: wordpress-app
    spec:
      containers:
        - name: wordpress
          image: wordpress:6.2.1-apache
          securityContext:
            capabilities:
              add: [ "SYS_ADMIN" ]
          ports:
            - containerPort: 80
              name: http-port
          volumeMounts:
            - name: wordpress-data
              mountPath: /var/www/html
          envFrom:
            - configMapRef:
                name: wordpress-cm
      volumes:
        - name: wordpress-data
          persistentVolumeClaim:
            claimName: wordpress-pvc
---
# Persistent volume - Dynamically provission using nfs server
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: wordpress-pvc
  labels:
    app: wordpress-app
spec:
  storageClassName: nfs-client
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
---
# ConfigMap
apiVersion: v1
kind: ConfigMap
metadata:
  name: wordpress-cm
  namespace: default
data:
  WORDPRESS_DB_NAME: wordpress
  WORDPRESS_DB_USER: root
  WORDPRESS_DB_PASSWORD: 'Password'
  WORDPRESS_DB_HOST: mysql-0.mysql.default.svc.cluster.local
  WORDPRESS_DEBUG: "true"
---
# Service
apiVersion: v1
kind: Service
metadata:
  name: wordpress
  namespace: default
spec:
  type: LoadBalancer
  selector:
    app: wordpress-app
  ports:
    - protocol: TCP
      port: 80
      targetPort: http-port

问题分析与解决思路 #

核心原因 #

挂载的NFS存储卷为空，WordPress镜像启动时默认将核心文件放在/usr/src/wordpress，但挂载卷到/var/www/html后，容器内原有目录内容被空卷覆盖，导致启动脚本无法复制wp-config.php，同时缺少wp-load.php等核心运行文件。

解决步骤 #

1. 初始化存储卷内容
   可以通过临时容器将WordPress核心文件复制到NFS目录：

   # 启动临时WordPress容器
   docker run --name temp-wordpress -d wordpress:6.2.1-apache
   # 复制核心文件到本地已挂载NFS的目录
   docker cp temp-wordpress:/usr/src/wordpress/ /path/to/nfs/wordpress-data/
   # 删除临时容器
   docker rm -f temp-wordpress
   

   也可以在Kubernetes Deployment中添加Init容器，自动完成文件复制：

   # 在Deployment的spec.template.spec中添加以下配置
   initContainers:
     - name: copy-wordpress-files
       image: wordpress:6.2.1-apache
       command: ["sh", "-c", "cp -r /usr/src/wordpress/* /var/www/html/ && chown -R www-data:www-data /var/www/html/"]
       volumeMounts:
         - name: wordpress-data
           mountPath: /var/www/html
   

2. 检查存储卷权限
   确保NFS目录权限符合WordPress运行要求，www-data用户需拥有读写权限，上述Init容器命令中已包含权限设置。

3. 验证部署
   重启WordPress Pod后，进入容器检查/var/www/html目录下是否存在wp-config.php、wp-load.php等文件，同时确认数据库连接配置正确。

内容的提问来源于stack exchange，提问作者Dev Fh