Master Kubernetes Contexts and Switch Clusters Efficiently with kubectx

What is a Kubernetes Context?

Kubernetes context determines which cluster, user identity, and default namespace you are operating on.

Configure Context for Production Cluster

Extract certificates from the admin.conf file and save them as ca.crt, tls.crt, and tls.key.

$ sudo cat /etc/kubernetes/admin.conf | awk '/certificate-authority-data/ {print $NF}' | base64 -d
$ sudo cat /etc/kubernetes/admin.conf | awk '/client-certificate-data/ {print $NF}' | base64 -d
$ sudo cat /etc/kubernetes/admin.conf | awk '/client-key-data/ {print $NF}' | base64 -d

Set the cluster, user, and context:

# 1. Set cluster and CA certificate
kubectl config set-cluster produce --server https://172.139.20.100:6443 --certificate-authority ca.crt

# 2. Set user credentials (certificate authentication)
kubectl config set-credentials prod-admin --client-certificate tls.crt --client-key tls.key

# 3. Add context
kubectl config set-context prod-ctx --cluster produce --user prod-admin
Context "prod-ctx" created.

Configure Context for Test Cluster

Similarly, extract certificates and configure the test cluster:

# 1. Set cluster and CA certificate
kubectl config set-cluster test --server https://172.139.20.96:6443 --certificate-authority ca.crt

# 2. Set user credentials
kubectl config set-credentials test-admin --client-certificate tls.crt --client-key tls.key

# 3. Add context
kubectl config set-context test-ctx --cluster test --user test-admin
Context "test-ctx" created.

Verify Contexts

Switch to each context and list nodes:

# Production
kubectl config use-context prod-ctx
kubectl get nodes

# Test
kubectl config use-context test-ctx
kubectl get nodes

Boost Switching Efficiency with kubectx

When many clusters exist, typing full context names is inefficient. Install kubectx:

$ wget https://github.com/ahmetb/kubectx/releases/download/v0.9.5/kubectx_v0.9.5_linux_x86_64.tar.gz
$ tar xvf kubectx_v0.9.5_linux_x86_64.tar.gz
$ sudo mv kubectx /usr/local/bin/

List all contexts and switch quickly:

$ kubectx
prod-ctx
test-ctx   # highlighted as current

$ kubectx prod-ctx
✔ Switched to context "prod-ctx"

Conclusion

As the number of Kubernetes clusters grows, using the context mechanism together with tools like kubectx turns you from an operator into an engineer, making cluster management more elegant, efficient, and less error‑prone.