K0s Cluster Without Internet Access
Let’s see how k0s makes the Air-Gap installation an easy process
🔥 Following several comments I had on LinkedIn, I must emphasize this article only covers a very simplified way to perform an air gap installation. It is not for sure a complete guide to setup a resilient / secure / observable / upgradable production cluster.
In companies with high security constraints, it might be needed to install a Kubernetes cluster on machines without any internet access. This means all the things needed to set up the cluster must be downloaded beforehand from another machine and then copied over to the Air-Gap machines in a secure way (for instance with a USB key thus through a physical access to the machine).
In this short article, we will see how k0s manages the Air Gap installation. This feature has been added in k0s 0.12 (mars 2021). We will illustrate the whole process with 2 VMs created with Multipass:
- the first one, named tools, has internet access. It will be used to get the k0s binary and all the images needed to setup a cluster
- the second one, named airgap, is a simulated Air Gap machine (we will suppose this one does not have an internet access)
