Etcd

Deep understanding of Kube-APIServer kube-apiserver is one of the most important core components of Kubernetes and mainly provides the following functions Provides REST API interface for cluster management, including authentication and authorization, data verification, cluster status changes, etc. Provides a hub for data interaction and communication between other modules (other modules query or modify data through API Server, only API Server directly operates etcd) apiserver main functions: Authentication: Use the cluster to determine identity. Authentication: Use operation CRUD, permissions are required. Access: For Kubernetes, some additional actions are required. For example, if the written value is not standardized, it needs to be modified, and verification is required after modification. Finally, it is necessary to limit the current flow to prevent maliciousness or loopholes from causing congestion. Mutating Validating +Admission Current Limit Implementation of APIServer object Access control API Server is the intermediate hub for all component interactions. ...

Before starting ETCD is the hardest of all components in Kubernetes because ETCD is stateful, not stateless. When I was doing k3s runtime design before, I learned some concepts about ETCD and Raft algorithms. As a prelude to knowledge, please go to [ETCD](https://docker.nsddd.top/Cloud-Native-k8s/24 .html) and Raft algorithm for prelude learning. **This article will explain ETCD and Raft in depth and throughout. And analyze ETCD in depth from the perspective of Kubernetes. ** ...