Kubernetes

Describe the sequence of events in case of creating a ReplicaSet

Difficulty: unrated

Source: bregman-arie/devops-exercises by Arie Bregman

Answer

  • The client (e.g. kubectl) sends a request to the API server to create a ReplicaSet
  • The Controller detects there is a new event requesting for a ReplicaSet
  • The controller creates new Pod definitions (the exact number depends on what is defined in the ReplicaSet definition)
  • The scheduler detects unassigned Pods and decides to which nodes to assign the Pods. This information sent to the API server
  • Kubelet detects that two Pods were assigned to the node it's running on (as it constantly watching the API server)
  • Kubelet sends requests to the container engine, to create the containers that are part of the Pod
  • Kubelet sends a request to the API server to notify it the Pods were created