Exercise

  1. Create a deployment named ghost with 3 pods based on the ghost:4 image

  2. Expose the deployment with a ClusterIP service

ℹ️
ghost application listens on port 2368

  1. From the service, retrieved the IP addresses of the pods

  2. Inspect the Endpoints resource created

  3. Delete the deployment and service

Documentation

https://kubernetes.io/docs/concepts/services-networking/service/


Solution
  1. Create a deployment with 3 pods based on the ghost:4 image
k create deploy ghost --image=ghost:4 --replicas=3
  1. Expose the deployment with a ClusterIP service
k expose deploy/ghost --port 2368
  1. From the service, retreived the IP addresses of the pods

The pods IP addresses are listed in the Endpoints property:

k describe svc/ghost
Name:              ghost
Namespace:         default
Labels:            app=ghost
Annotations:       <none>
Selector:          app=ghost
Type:              ClusterIP
IP Family Policy:  SingleStack
IP Families:       IPv4
IP:                10.110.190.83
IPs:               10.110.190.83
Port:              <unset>  2368/TCP
TargetPort:        2368/TCP
Endpoints:         10.32.0.3:2368,10.38.0.3:2368,10.38.0.5:2368   <- pods' IP addresses
Session Affinity:  None
Events:            <none>
  1. Inspect the Endpoints resource created

When creating the service a Endpoints resource have been created as well. It lists the IP:PORT of pods in the Ready status and can be described like any other Kubernetes resources:

k describe  Endpoints ghost
Name:         ghost
Namespace:    default
Labels:       app=ghost
Annotations:  <none>
Subsets:
  Addresses:          10.32.0.3,10.38.0.3,10.38.0.5
  NotReadyAddresses:  <none>
  Ports:
    Name     Port  Protocol
    ----     ----  --------
    <unset>  2368  TCP

Events:  <none>
  1. Delete the deployment and service
k delete deploy/ghost svc/ghost