Sometimes when working with a new Kubernetes cluster you will be given a config file to use when authenticating with the cluster. This file should be placed at ~/.kube/config. However you may already have an existing config file at that location and you need to merge them together.
Here is a quick command you can run to merge your two config files.
Note: For the example below I’m going to assume the new config file is called
~/.kube/new_config and the existing config file is called
Make a copy of your existing config
cp ~/.kube/config ~/.kube/config_bk
Merge the two config files together into a new config file
KUBECONFIG=~/.kube/config:~/.kube/new_config kubectl config view --flatten > ~/.kube/config_tmp
Replace your old config with the new merged config
mv /tmp/config ~/.kube/config
(optional) Delete the backup once you confirm everything worked ok
Here is all of that (except the cleanup) as a one-liner.
cp ~/.kube/config ~/.kube/config_bk && KUBECONFIG=~/.kube/config:~/.kube/new_config kubectl config view --flatten > ~/.kube/config_tmp && mv /tmp/config ~/.kube/config