Setting up Kubernetes in DigitalOcean

August 18, 2017

In the following, we’re going to show you how to use kubicorn to ramp up a Kubernetes cluster in DigitalOcean, use it and tear it down again. The cluster will be running over DigitalOcean private networking.

As a prerequisite, you need to have kubicorn installed. Since we don’t have binary releases yet, we assume you’ve got Go installed and simply do:

Installing

$ go get github.com/kubicorn/kubicorn

The first thing you will do now is to define the cluster resources. For this, you need to select a certain profile. Of course, once you’re more familiar with kubicorn, you can go ahead and extend existing profiles or create new ones. In the following we’ll be using an existing profile called do, which is a profile for a cluster in DigitalOcean.

Creating

Now execute the following command:

$ kubicorn create myfirstk8s --profile do

Verify that kubicorn create did a good job by executing:

$ cat _state/myfirstk8s/cluster.yaml

Feel free to tweak the configuration to your liking here.

Authenticating

We’re now in a position to have the cluster resources defined, locally, based on the selected profile. Next we will apply the so defined resources using the apply command, but before we do that we’ll set up the access to DigitalOcean. You will need a DigitalOcean access token. You can use this guide to create an access token.

Next, export the environment variable DIGITALOCEAN_ACCESS_TOKEN so that kubicorn can pick it up in the next step:

$ export DIGITALOCEAN_ACCESS_TOKEN=*****************************************

Also, make sure that the public SSH key for your DigitalOcean account is called id_rsa.pub, which is the default in above profile:

$ ls -al ~/.ssh/id_rsa.pub
-rw-------@ 1 mhausenblas  staff   754B 20 Mar 04:03 /Users/mhausenblas/.ssh/id_rsa.pub

Applying

With the access set up, we can now apply the resources we defined in the first step. This actually creates resources in DigitalOcean. Up to now we’ve only been working locally.

So, execute:

$ kubicorn apply myfirstk8s

Now kubicorn will reconcile your intended state against the actual state in the cloud, thus creating a Kubernetes cluster. A kubectl configuration file (kubeconfig) will be created or appended for the cluster on your local filesystem. You can now kubectl get nodes and verify that Kubernetes 1.7.0 is now running. You can also ssh into your instances using the example command found in the output from kubicorn

Deleting

To delete your cluster run:

$ kubicorn delete myfirstk8s

Congratulations, you’re an official kubicorn user now and might want to dive deeper, for example, learning how to define your own profiles.