k3s/cluster/cloudimages

Kubernetes-optimized images

This directory contains manifests for building Kubernetes-optimized images for various clouds (currently just AWS). It is currently highly experimental, and these images are not used by default (though you can pass AWS_IMAGE to the AWS kube-up script if you're feeling brave).

Advantages of an optimized image:

• We can preinstall packages that would otherwise require a download. Great for speed, and also for reliability (in case the source repository is down)
• We can make kernel configuration changes that might otherwise require a reboot, or even apply kernel patches if we really want to. For example, Debian requires a kernel boot parameter to enable the cgroup memory controller, which we require.
• The more configuration we can do in advance, the easier it is for people that don't want to use kube-up to get a cluster up and running.

Advantages of a harmonized image:

• All the platforms can test with the same versions of software, rather than relying on whatever image happens to be optimal on that cloud.

bootstrap-vz

Currently images are built using bootstrap-vz, because this is default builder for the official Debian images, and because it supports multiple clouds including AWS, Azure & GCE. It also supports KVM, which should support OpenStack.

Building an image

A go program/script to build images in in progress, in the contrib project.