I am running Kubernetes in GKE and I created a default ingress for one of my services, however I am unable to access my service, because ingress default healthcheck (the one that expects to receive a 200 return code when it queries the root path: /) is not working.

The reason for this is that my service is returning 400 on the root path (/), because it expects to receive a request with a specific Host header, like: Host: my-api.com. How do I configure my ingress to add this header to the root healthcheck?

Note: I managed to configure this in the GCP console, but I would like to know how can I configure this on my yaml, so that I won't have to remember to do this if I have to recreate my ingress.

Ingress:

---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress
  namespace: backend
  annotations:
    kubernetes.io/ingress.global-static-ip-name: "backend"
    networking.gke.io/managed-certificates: "api-certificate"
spec:
  rules:
  - host: my-api.com
    http:
      paths:
      - path: /*
        backend:
          serviceName: backend-service
          servicePort: http

Service:

---
apiVersion: v1
kind: Service
metadata:
  name: backend-service
  namespace: backend
  annotations:
    beta.cloud.google.com/backend-config: '{"ports": {"80":"backend-web-backend-config"}}'
spec:
  selector:
    app: backend-web
  ports:
  - name: http
    targetPort: 8000
    port: 80
  type: NodePort

Backend Config:

apiVersion: cloud.google.com/v1beta1
kind: BackendConfig
metadata:
  name: backend-web-backend-config
  namespace: backend
spec:
  timeoutSec: 120

Deployment:

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: backend-web
  namespace: backend
  labels:
    app: backend-web
spec:
  selector:
    matchLabels:
      app: backend-web
  template:
    metadata:
      labels:
        app: backend-web
    spec:
      containers:
      - name: web
        image: backend:{{VERSION}}
        imagePullPolicy: IfNotPresent
        ports:
          - containerPort: 8000
            protocol: TCP
        command: ["run"]
        resources:
          requests:
            memory: "800Mi"
            cpu: 150m
          limits:
            memory: "2Gi"
            cpu: 1
        livenessProbe:
          httpGet:
            httpHeaders:
              - name: Accept
                value: application/json
            path: "/healthcheck"
            port: 8000
          initialDelaySeconds: 15
          timeoutSeconds: 5
          periodSeconds: 30
        readinessProbe:
          httpGet:
            httpHeaders:
              - name: Accept
                value: application/json
            path: "/healthcheck"
            port: 8000
          initialDelaySeconds: 15
          timeoutSeconds: 5
          periodSeconds: 30