K8s Controllers

Table of Contents

1. Overview

1. Overview

Controllers: Automated systems managing the state of Kubernetes clusters.
Essential for maintaining Kubernetes operations.
Automates the repetitive and complex tasks.
Key to achieving scalable and reliable container orchestration.
see https://kubernetes.io/docs/concepts/architecture/controller/

1.1. Core Functionality

State Reconciliation: Compare current state to desired state.
Actions:
- Deploy
- Mount volumes
- Manage scaling
- Handle failures

1.2. Mechanism

Control Loop: Continuously monitors and updates cluster state.
Work Queue: Stores observations/changes for processing.
Reconcile Loop: Processes items from Work Queue to align with desired state.

1.3. Epistemological Correlations

Control Theory: Similar to control systems in engineering.
Homeostasis in Biology: Maintains stable internal environment despite external changes.

Tags::cs: