502 Bad Gateway with Kubernetes Ingress

Question

I have a kubernetes setup with the configuration like below:

#--- kind: Service apiVersion: v1 metadata:   name: myservice spec:   selector:     app: my-service   ports:     - protocol: "TCP"       # Port accessible inside cluster       port: 8080       # Port to forward to inside the pod       targetPort: 80    --- apiVersion: extensions/v1beta1 kind: Deployment metadata:   name: my-service spec:   replicas: 1   template:     metadata:       labels:         app: my-service     spec:       containers:         - name: my-service           image: my-custom-docker-regisry/my-service:latest           imagePullPolicy: Always           ports:             - containerPort: 8080       imagePullSecrets:       - name: regcred 

and my ingress:

apiVersion: extensions/v1beta1 kind: Ingress metadata:   name: test-ingress   annotations:     nginx.ingress.kubernetes.io/ssl-redirect: "false" spec:   rules:   - http:       paths:       - path: /myservice         backend:           serviceName: myservice           servicePort: 80 

What I tried to do is pulling the image from my docker registry and run it in the kubernetes. I have configured here one deployment and one service and expose the service to the outside with the ingress.

My minikube is running under ip 192.168.99.100 and when I tried to access my application with address: curl 192.168.99.100:80/myservice, I got 502 Bad Gateway.

Does anyone have an idea why it happended or did I do something wrong with the configuration? Thank you in advanced!

Answer 1

Your ingress targets this service:

     serviceName: myservice      servicePort: 80 

but the service named myservice exposes port 8080 rather than 80:

  ports:     - protocol: "TCP"       # Port accessible inside cluster       port: 8080       # Port to forward to inside the pod       targetPort: 80 

Your ingress should point to one of the ports exposed by the service.

Also, the service itself targets port 80, but the pods in your deployment seem to expose port 8080, rather than 80:

  containers:     - name: my-service       image: my-custom-docker-regisry/my-service:latest       imagePullPolicy: Always       ports:         - containerPort: 8080 

So long story short, looks like you could swap port with targetPort in your service so that:

• the pods expose port 8080
• the service exposes port 8080 of all the pods under service name myservice port 80,
• the ingress configures nginx to proxy your traffic to service myservice port 80.