In this lab you will deploy the DNS add-on which provides DNS based service discovery to applications running inside the Kubernetes cluster.
Deploy the kube-dns
cluster add-on:
kubectl create -f https://raw.githubusercontent.com/lpmi-13/kubernetes-the-hard-way-do/main/deployments/core-dns.yaml
output
service "kube-dns" created
serviceaccount "kube-dns" created
configmap "kube-dns" created
deployment.extensions "kube-dns" created
List the pods created by the kube-dns
deployment:
kubectl get pods -l k8s-app=kube-dns -n kube-system
output
NAME READY STATUS RESTARTS AGE
coredns-7cb4c7458d-p7hxn 3/3 Running 0 20s
Create a dnsutils
pod
kubectl run busybox --image=busybox:1.28.4 --restart=Never -- sleep 3600
Verify that the pod is running:
kubectl get pod busybox
Output:
NAME READY STATUS RESTARTS AGE
busybox 1/1 Running 0 45s
Execute a DNS lookup for the kubernetes
service inside the dnsutils
pod:
kubectl exec -it busybox -- nslookup kubernetes
output
Server: 10.32.0.10
Address 1: 10.32.0.10 kube-dns.kube-system.svc.cluster.local
Name: kubernetes
Address 1: 10.32.0.1 kubernetes.default.svc.cluster.local
Next: Smoke Test