GKE Ingress无法连接WordPress后端服务，显示后端状态异常求助

我正在Google Kubernetes Engine（GKE）上部署WordPress，除Ingress组件外其余部署环节均正常，但Ingress无法连接后端服务，控制台显示**"SOME BACKEND SERVICES ARE IN UNHEALTHY STATE"**。现将相关配置文件及GCP资源信息附上，恳请技术人员协助排查问题：

WordPress Deployment配置文件 #

apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress-deployment
  labels:
    app: wordpress
spec:
  replicas: 1
  selector:
    matchLabels:
      app: wordpress
  template:
    metadata:
      labels:
        app: wordpress
    spec:
      containers:
      - name: wordpress
        image: wordpress
        ports:
        - containerPort: 80
        volumeMounts:
          - name: wordpress-persistent-storage
            mountPath: /var/www/html
        env:
        - name: WORDPRESS_DB_HOST
          value: mysql-service
        - name: WORDPRESS_DB_USER
          value: wpuser
        - name: WORDPRESS_DB_PASSWORD
          value: pass@123
        - name: WORDPRESS_DB_NAME
          value: wpdb
        - name: WORDPRESS_DEBUG
          value: "1"
      volumes:
        - name: wordpress-persistent-storage
          persistentVolumeClaim:
            claimName: wordpress-volumeclaim

Service配置文件 #

apiVersion: v1
kind: Service
metadata:
  name: wordpress-service
spec:
  type: NodePort
  selector:
    app: wordpress
  ports:
  - name: portname
    nodePort: 30100
    port: 80
    targetPort: 80

Ingress配置文件 #

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: wordpress-ingress
  annotations:
    kubernetes.io/ingress.global-static-ip-name: my-address
    networking.gke.io/managed-certificates: managed-cert
    kubernetes.io/ingress.class: "gce"
spec:
  rules:
    - host: example.com 
    - http:
        paths:
        - path: /
          pathType: Prefix
          backend:
            service:
              name: wordpress-service
              port:
                number: 80

相关GCP资源信息 #

• GCP控制台Ingress状态截图（共2张）
• GCP日志信息

内容的提问来源于stack exchange，提问作者Noor Muradi