The -n flag

Learn to specify a Namespace with the -n flag.

The -n flag

kubectl commands run by default in the active context's namespace (usually default). For another namespace, -n (--namespace) is added to each command:

kubectl get pods -n dev
kubectl apply -f web.yaml -n dev        # if the YAML has no namespace
kubectl logs deploy/web -n prod
kubectl exec -it -n prod deploy/web -- sh

If metadata.namespace is written in the YAML and -n differs, kubectl errors.

Where does the flag go?

-n can be written anywhere in the command; but in exec and run commands it must come before --, otherwise it counts as an argument of the command in the container:

kubectl -n prod get pods              # right
kubectl get pods -n prod              # right
kubectl exec deploy/web -n prod -- ls # right
kubectl exec deploy/web -- ls -n prod # wrong: -n goes to ls

Exercise Work in another namespace

Write three commands: list the pods in the dev namespace; apply web.yaml to the dev namespace; show the logs of the web deployment in the prod namespace (deploy/web).

Show example solution

kubectl get pods -n dev
kubectl apply -f web.yaml -n dev
kubectl logs deploy/web -n prod

Test yourself

What is the difference between kubectl get pods -n dev and kubectl get pods?
- The first lists the pods in dev, the second those in the active context's namespace
- There is no difference
- The second lists all namespaces
- The first shows a pod named dev
Show answer

The first lists the pods in dev, the second those in the active context's namespace — -A is needed for all namespaces.

Run the command in the prod namespace.

kubectl logs deploy/web ____ prod

Show answer

kubectl logs deploy/web -n prod

Match.

-n dev

Namespace for one command
-A

All namespaces
before --

Where -n goes (exec)
metadata.namespace

Namespace in YAML

Next lesson: Default Namespace

We Are Enhancing Your Experience

Cookie Preferences

Strictly Necessary Cookies

Analytical Cookies