Openshift Container Platform 4: Service(SVC) networking troubleshooting of generic issues of communication.

Issue

A service is an abstraction that presents a unified network interface that is backed by one or more pods. If in OCP the microservices need to talk to each other internally without exposing routes to the outside world, the "service" object is used and needed. These microservices interact via the Kubernetes "service" API, which acts as a load balancer that resolves a set of pods to a single IP.

While OpenShift and the service API work together to abstract most of the complexity behind networking, problems can still arise when trying to interact with other microservices deployed on OpenShift

For the examples, we’ll assume a basic app consisting of a single ClusterIP Service and Deployment, each called hello-world. The following service will be used as an example for each issue described in this post.

apiVersion: v1
kind: Service
metadata:
  name: hello-world
  namespace: my-namespace
spec:
  selector:
    app: hello-world
  ports:
    - name: https
      protocol: TCP
      port: 443
      targetPort: 8443