Working towards self-hosting of k8s, we will likely have to add some
features to kubelet, such as independent mounting of disks or copying of
resources from S3. protokube lets us develop those features prior to
moving them into kubelet.
In particular, today we need to mount an EBS volume on the master prior
to starting kubelet, if we want to run the master in an ASG.
protokube is a service that runs on boot, and it tries to mount the
master volume. Once it mounts the master volume, it runs kubelet.
Currently it runs kubelet by looking at a directory
/etc/kubernetes/bootstrap; the intention is that we could actually have
multiple versions of kubelet in here (or other services) and then we
could automatically roll-back from a failed update.
Justin Santa Barbara