Fix docs - enabling RBAC for minikube

[jwerak]

Describe what this PR does and why we need it:

Updates documentation for starting minikube:

• enabling RBAC for minikube
• removing specified version (minikube has only 1.9.0 or latest, current 1.9.3 didn't work)

Changes proposed in this pull request

only docs changes above

Does this PR depend on another PR (Use this to track when PRs should be merged)

no

Which issue this PR fixes (This will close that issue when PR gets merged)

none

[djzager]

Thank you for the submission @jwerak .

[mhrivnak]

Hold on with this. I'll explain shortly.

[mhrivnak]

Thank you for this PR!

I suspect you were using the localkube bootstrapper. It has fallen out of favor and is being deprecated in favor of kubeadm. The instructions in the README work well with kubeadm but won't work with localkube.

You probably hit the same issue as this person: kubernetes/minikube#2040

When using kubeadm, RBAC is on by default. To make matters confusing, kubeadm takes different options to --extra-config, and it fails if you try to enable RBAC the way you would with localkube.

kubeadm does allow you to specify any recent version of kubernetes, unlike localkube.

In sum, I think if there is an improvement to make for this README, it would be to clarify that kubeadm should be used as the bootstrapper.

[djzager]

@mhrivnak Do you have a link to how to use the kubeadm bootstrapper?

[djzager]

Found it 😎 , minikube profile --help

[jwerak]

@mhrivnak Thanks, I've had no idea about custom bootstrap in minikube, good to know, thanks 👍

I've tested following is working for me now:

minikube start --bootstrapper kubeadm
# AND 
minikube start --bootstrapper kubeadm --kubernetes-version v1.9.4

Should I keep the version with version or without?

[mhrivnak]

Should I keep the version with version or without?

I like making it clear that setting the version is an option, and I recommend doing so as a normal practice. minikube makes it easy to iterate on standing up and tearing down a cluster. You'd hate to suddenly start getting 1.10 instead of 1.9, which changes something you depended on; you might not realize that a version change happened at all, and if it did break something, once you figured out that a version change was responsible, you might not know which version you were running before.

TL;DR it seems worth setting the version explicitly to get a consistent and reliable experience. But maybe that should be called out in the documentation more directly.

Does that make sense? What do you think?

[jwerak]

@mhrivnak consistent and reliable makes sense to me too, new commit has landed.

[mhrivnak]

Is this line intended to be here?

[jwerak]

ups, little advertisement can't hurt they say.
Sorry for that.
It's gone now.

[jmrodri]

+1 to @mhrivnak comments