Write some documentation

• motivation:
  • designed for people doing research around kubernetes and its ecosystem (and not just using kubernetes to deploy applications)
  • compared to k3s: k3s is not compatible with some third-party tools (Istio, CNI). But enos-kubernetes takes longer to deploy.
  • Kubespray is very flexible: all kubespray variables are available, including changing the version of kubernetes (link to their doc). Soon you will be able to also select the version of kubespray, which is useful because each kubespray version has min/max constraints on its dependencies (kubernetes, ansible, etc)
  • might be useful for deploying a custom kubernetes cluster on cloud providers VMs, while delegating some managed service to the cloud provider (storage, network, load balancer). Kubespray supports this.
• explain the relation between enoslib roles and kubespray groups
  • it generates a full ansible inventory (point to example inventories given with kubespray + doc of all the groups)
• how to configure kubespray (link to example kubespray inventories)
  • e.g. container_manager, container storage dir
• simple example on g5k (add config to use the G5K registry cache)
• simple example on chameleon
• example with advanced kubespray config (CNI, dual stack)
• example with a custom kubespray version + custom kubernetes version
• example using existing hosts (static provider of enoslib). Give an example with cloudlab
• complex python example with G5K:
  • enable IPv6 (play_on : dhclient -6 + sysctl net.ipv6.conf.all.accept_ra)
  • deploy kubespray
  • do some more actions after deploying
  • use iostio dual-stack doc (ask Guillaume)