How to set the Pod DNS in Kubernetes

Question

I wanted to know if there is any way that I can set a DNS for the Pod in the StatefulSet, so I can call them directly.

I have read the Kubernetes documentation, but I haven't seen anything useful.

Answer 1

You can directly hit the POD if using the statefulset with headless service

So if you have three replicas running web-0, web-1, web-2 you can use curl

web-0.<service-name>.<namespace-name>.svc.cluster.local

POD name

<pod-name>.<service-name>.<namespace-name>.svc.cluster.local

But the important part is your service should be headless

Example

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  ports:
  - port: 80
    name: web
  clusterIP: None
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: "nginx"
  replicas: 3 
  minReadySeconds: 10 
  template:
    metadata:
      labels:
        app: nginx 
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: registry.k8s.io/nginx
        ports:
        - containerPort: 80
          name: web

Official doc ref : https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/#stable-network-id