How to Forward Traffic to External Cluster with Kubernetes Service and Ingress

Goal

• I have external endpoint that need to be accessed via kubernetes ingress
• Utilize nginx ingress as Reverse Proxy
• Utilize Cert Manager that already has Let's Encrypt SSL Certificate

How-to

• Create Kubernetes Service

apiVersion: v1
kind: Service
metadata:
  name: gitlab-api
  namespace: tools
spec:
  type: ExternalName
  externalName: 192.168.0.162
  ports:
    - port: 8443
      targetPort: 8443

• Create Ingress and Pointed to Service

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: gitlab-api
  namespace: tools
  annotations:
    nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
    nginx.ingress.kubernetes.io/proxy-ssl-verify: "false"
spec:
  ingressClassName: nginx
  tls:
    - hosts:
        - gitlab.lukmanlab.com
      secretName: wcard-lukmanlab-com-tls
  rules:
  - host: gitlab.lukmanlab.com
    http:
      paths:
      - backend:
          service:
            name: gitlab-api
            port:
              number: 8443
        path: /
        pathType: ImplementationSpecific

Note

• In this article, we also learn how bypass or not verify SSL of server origin.
• And, we also learn how we reverse proxy GitLab Server via Kubernetes Ingress.