Upgrade/1.24

[fireflycons]

There were a lot of changes to get to here from 1.13!

OS Changes

• Upgrade to Ubuntu 22.04
• Set linux kernel switch (from Vagrant) to disable cgroups v2, the default for Ubuntu 22.04 (should be fully supported by kubernetes in 1.25)

Kube changes

• Docker deprecation - use containerd/runc/CNI plugins
• etcd upgrade (3.5.3)
• Many command line switch changes, deprecations, moving to config YAML
• Certificate subject/x509 extension updates

My own changes

I've made a few what I'd like to think are improvements:

• Optimize vagrantfile

  • Change memory allocations (master-1 needs more if it is to run e2e, master-2 can have less, workers need more as services are bigger)
  • Use local ruby functions to be DRY.

• Secure the PKI

  • Make it all owned by root and mode 600
  • Place in /var/lib/kubernetes/pki
  • Make all the service kubeconfigs refer to certs by path rather than embed. In the real world this makes cert rotation easier.
  • Have only one copy of the CA cert. Link to it where it appears elsewhere (etcd)
    • Use shell variables for IP addresses and ranges so if a student wants to change locally, it's an easy search/replace
    • Compute things like cluster DNS from above shell vars to other shell vars.

Other Changes

• Update external documentation links