How to change kubernetes default namespace for issuing commands

Kubernetes

By Vikrant

July 8, 2018

How to change the default namespace for issuing the kubernetes command?

Check the current config view, t’s showing current-context as minikube.

$ kubectl config view
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: REDACTED
    server: https://172.17.1.101:6443
  name: cluster.local
- cluster:
    certificate-authority: /Users/viaggarw/.minikube/ca.crt
    server: https://192.168.99.101:8443
  name: minikube
contexts:
- context:
    cluster: cluster.local
    user: admin-cluster.local
  name: admin-cluster.local
- context:
    cluster: minikube
    user: minikube
  name: minikube
current-context: minikube
kind: Config
preferences: {}
users:
- name: admin-cluster.local
  user:
    client-certificate-data: REDACTED
    client-key-data: REDACTED
- name: minikube
  user:
    client-certificate: /Users/viaggarw/.minikube/client.crt
    client-key: /Users/viaggarw/.minikube/client.key

Export the current context into variable.

$ export CURRENT_CONTEXT=$(kubectl config view|awk '/current-context/ {print $2}')
$ echo $CURRENT_CONTEXT

Modify the current “default” namespace context to “kube-system” namespace.

$ kubectl config set-context $CURRENT_CONTEXT --namespace=kube-system
Context "minikube" modified.

Check the output of the command again, it’s still showing minikube.

$ kubectl config view
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: REDACTED
    server: https://172.17.1.101:6443
  name: cluster.local
- cluster:
    certificate-authority: /Users/viaggarw/.minikube/ca.crt
    server: https://192.168.99.101:8443
  name: minikube
contexts:
- context:
    cluster: cluster.local
    user: admin-cluster.local
  name: admin-cluster.local
- context:
    cluster: minikube
    namespace: kube-system
    user: minikube
  name: minikube
current-context: minikube
kind: Config
preferences: {}
users:
- name: admin-cluster.local
  user:
    client-certificate-data: REDACTED
    client-key-data: REDACTED
- name: minikube
  user:
    client-certificate: /Users/viaggarw/.minikube/client.crt
    client-key: /Users/viaggarw/.minikube/client.key

Now issuing any command without specifying the namespace will issue the command in kube-system namespace instead of default namespace.

$ kubectl get pod
NAME                                        READY     STATUS    RESTARTS   AGE
default-http-backend-59868b7dd6-55x77       1/1       Running   2          2d
etcd-minikube                               1/1       Running   0          11h
heapster-l6g7t                              1/1       Running   0          11h
influxdb-grafana-jq6mp                      2/2       Running   0          11h
kube-addon-manager-minikube                 1/1       Running   2          2d
kube-apiserver-minikube                     1/1       Running   0          11h
kube-controller-manager-minikube            1/1       Running   0          11h
kube-dns-79f5cdddc5-qq62q                   3/3       Running   0          11h
kube-proxy-854rs                            1/1       Running   0          11h
kube-scheduler-minikube                     1/1       Running   1          1d
kubernetes-dashboard-5498ccf677-pdw4g       1/1       Running   6          2d
metrics-server-85c979995f-wm5br             1/1       Running   0          11h
nginx-ingress-controller-67956bf89d-2chmj   1/1       Running   7          2d
storage-provisioner                         1/1       Running   6          2d