Namespaces

Namespaces lets you isolate group of resources within a single cluster.

Default Kubernetes Namespace

These namespaces gets created automatically when a cluster is created:

• default
• kube-system
• kube-public
• kube-node-lease

Get namespaces: kubectl get namespaces

CLI Commands

Get all objects in default namespace: kubectl get all

Show all resources from all namespaces: kubectl get all- namespaces

Services from a specific namespace: kubectl svc -n kube-system

Create namespace: kubectl create ns kubekart

And run a pod: kubectl run nginx1 --image=nginx -n kubekart

Get pod from your namespace: kubectl get podf -n kubekart

Delete a namespace: kubectl delete ns kubekart

Specify Namespace in Definition File:

cat pod1.yaml

apiVersion: v1
kind: Pod
metadata:
  name: nginx12
  namespace: kubekart
  labels:
    app: frontend
    project: infinity
spec:
  containers:
    - name: httpd-container
      image: httpd
      imagePullPolicy: IfNotPresent
      ports:
        - name: http-port
          containerPort: 8080 # exposed port

kubectl apply -f pod1.yaml

Extra namespaces example:

• dev
• prod

Change prefered namespace in kubeconfig file

kubectl config set-context --current --namespace=<insert-namespace-name-here>
# Validate
kubectl config view --minify | grep namespace: