Set/Switch the Default namespace when using kubectl

First get all the namespaces available:

> kubectl get ns
NAME              STATUS   AGE
cattle-system     Active   53d
default           Active   53d
development       Active   52d
heptio-sonobuoy   Active   33d
ingress-nginx     Active   53d
kube-node-lease   Active   53d
kube-public       Active   53d
kube-system       Active   53d
wordpress         Active   33d

To set the default namespace when using kubectl:

kubectl config set-context --current --namespace=ingress-nginx

Sources