DevOps Classroom Series – 07/Feb/2020

Kubernetes

Where is it used?

• For any container deployments which require
  • automatic scaling
  • micro services
  • volumes mounted to EBS, Azure Disks or most of third party virtual disks
  • Zero down time deployments
  • Effective Load Balancer integrations

Why Kubernetes

• It was written by Google and then they made it OpenSource.
• Google has inhouse products
  • Borg
  • Omega
• Kubernetes is build based out of google’s experiences with Borg and Omega.
• Kubernetes runs anywhere (AWS, Azure, IOT , Linux, Windows, etc..)

Basic Working Style on Kubernetes

• Create manifests (Specifications) with minimal information which will be desired state.
• This manifest will be written in YAML.

Kubernetes Architecture (First View)

• User connects with Kubernetes Master and Master gets the work done (desired state == actual state) on nodes (minions).
• Kubernetes has two popular ways of communication to master from user
  • Command line:
    • kubectl is the command line tool
    • kubectl works in declarative and imperative way
      • for declarative way we use YAML
  • Rest API
    • JSON based Rest API is exposed

Pet vs Cattle