Introduction

Since a DevOps engineer needs to manage multiple kubernetes clusters, here is a quick walkthrough to merge Kubernetes Kubectl config files thus allowing us to keep only one Kubectl config file in (~/.kube/config). Here's how to set this up step by step:

Make a copy of your existing config

cp ~/.kube/config ~/.kube/config.bak

Merge the two config files together into a new config file

KUBECONFIG=~/.kube/config:/path/to/new/config

kubectl config view --flatten > /tmp/config

This tells kubectl to use both config files (~/.kube/config and /path/to/new/config) together they are merged virtually for the following command.

This does the following:

• kubectl config view: Displays the merged configuration from all the files listed in KUBECONFIG.
• --flatten: Ensures that all referenced files (like user auth info or clusters that may point to separate files) are flattened into a single self-contained config file.
• /tmp/config: Redirects the output into a new standalone kubeconfig file.

You now have a new file at /tmp/config that:

• Includes all contexts, users, and clusters from both original kubeconfig files.
• Is self-contained (no external references).
• Can be used as a unified kubeconfig by itself.

Replace your old config with the new merged config

mv /tmp/config ~/.kube/config

This command moves the merged kubeconfig you created earlier from /tmp/config to your default kubeconfig location ~/.kube/config, effectively replacing your existing kubeconf

After Running

You can verify everything worked by running:

kubectl config get-contexts