Resources

1. Chapter 1 of the training course please refer to

Notes

Kubernetes builds on Borg and the lessons learned by Google for operating Borg for over 15 years.

Borg was used by Google internally to manage its systems

For more information here is the full paper https://research.google/pubs/pub43438/

• Borg has inspired current data centers and container runtime

Main Node

Where does the orchestration come in?

• Managed by several operators and controllers — will look at operators and controllers later one. Operators make use of custom resources to manage an application and their components.
• "Each controller interrogates the kube-apiserver for a particular object state, modifying the object until the declared state matches the current state." In short, controllers are used to ensure a process is happening in the desired way.
• "The ReplicaSet is a controller which deploys and restarts containers, Docker by default, until the requested number of containers is running." In short, its purpose is to ensure a specific number of nodes are running