在 Kubernetes 中运行 PostgreSQL 部署时出错：数据目录“没有这样的文件或目录”

Question

我正在尝试使用 Kubernetes 部署 PostgreSQL 数据库，但遇到了与数据目录相关的错误。以下是我对部署的 YAML 配置：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: db
spec:
  replicas: 1
  selector:
    matchLabels:
      app: db
  template:
    metadata:
      labels:
        type: deployment
        app: db
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                  - key: affinity-type
                    operator: In
                    values:
                      - postgres
      tolerations:
        - key: "key"
          value: "database"
          operator: "Equal"
          effect: "NoSchedule"
      volumes:
        - name: db-nfs-pvc
          persistentVolumeClaim:
            claimName: db-nfs-pvc
        - name: init-volume
          configMap:
            name: db-init
        - name: db-hba-conf
          configMap:
            name: hba-init
        - name: db-postgresql-conf
          configMap:
            name: postgresql-conf-init
      containers:
        - name: db
          image: postgres:14-bullseye
          imagePullPolicy: IfNotPresent
          ports:
            - containerPort: 5432
          envFrom:
            - secretRef:
                name: db
          volumeMounts:
            - name: db-nfs-pvc
              mountPath: /var/lib/postgresql/data
              subPath: pgdata
            - name: init-volume
              mountPath: /docker-entrypoint-initdb.d/
            - name: db-postgresql-conf
              mountPath: /var/lib/postgresql/data/postgresql.conf
              subPath: postgresql.conf
            - name: db-hba-conf
              mountPath: /var/lib/postgresql/data/pg_hba.conf
              subPath: pg_hba.conf
          command:
            - "postgres"
            - "-c"
            - "config_file=/var/lib/postgresql/data/postgresql.conf"
            - "-c"
            - "hba_file=/var/lib/postgresql/data/pg_hba.conf"

PostgreSQL_环境变量：

POSTGRES_USER=admin
POSTGRES_PASSWORD=password
PGDATA=/var/lib/postgresql/data/pgdata

问题：使用上述配置部署 PostgreSQL 数据库后，pod 无法启动，日志显示以下错误：

postgres: could not access directory "/var/lib/postgresql/data/pgdata": No such file or directory
Run initdb or pg_basebackup to initialize a PostgreSQL data directory.

kubectl 描述 pod：

0/11 nodes are available: pod has unbound immediate PersistentVolumeClaims. preemption: 0/11 nodes are available: 11 No preemption victims found for incoming pod.

附加信息：

• 我已验证 PersistentVolumeClaim db-nfs-pvc 已绑定且可用。
• 我已经包含了环境变量 POSTGRES_USER、POSTGRES_PASSWORD 和 PGDATA 来指定 PostgreSQL 用户、密码和数据目录路径。