kolm - Kubernetes on your local machine

kolm is a tool for running a Kubernetes 'cluster' consisting of an etcd and a kube-apiserver on your local machine. The primary use of kolm is for testing aggregated api servers, as debugging aggregated api servers in-cluster is a complex and troublesome task.

⚠️ kolm is a testing-only tool. Practices employed in this tool are inherently unsafe and should never be used in production and is plumbing-only.

Installation

To install kolm, simply run

go install github.com/onmetal/kolm/cmd/kolm@latest

👆 For now, kolm also requires etcd and kube-apiserver to be on your path. This will change in the future with automated binary management but wasn't implemented in the initial scope.

Usage

Controlling your apis

kolm has the primary type called api. An api is the previously mentioned 'cluster' with only a kube-apiserver and etcd.

The create such an api, simply run

kolm create api

This will create an api called kolm. Your kubeconfig will be modified to contain an entry pointing towards the new kolm cluster.

Once created, you can now start the api:

kolm start api

This runs the etcd and kube-apiserver. Both are running until terminated or the user interrupts via ctrl-c.

To remove an api, simply run

kolm delete api

All the previously described steps can also be done in a one-shot manner with:

kolm run api --rm

Using your api with an aggregated api server

If you have an aggregated api server & its APIServices at hand, you can let them 'join' your api. To do so, in a new terminal, first install your APIServices:

kolm apply apiservices <path-to-apiservices-directory>

Then, start your api server with flags similar to the following:

<my-server> \
  --etcd-servers=$(kolm get etcd-address) \
  --kubeconfig=$HOME/.kube/config \
  --authentication-kubeconfig=$HOME/.kube/config \
  --authorization-kubeconfig=$HOME/.kube/config \
  --tls-private-key-file $(kolm get host-key) \
  --tls-cert-file $(kolm get host-cert) \
  --secure-port=6443 \
  --feature-gates=APIPriorityAndFairness=false

After a short while, your api server should have joined the api.