Docker Overview and Structure

Docker Overview

• Docker is a platform for creating applications
• Docker offers multiple configurable/server environments in one
• Docker uses container technology

Docker Structure

• Hypervisor Type 1 (bare metal hypervisor): The virtualization layer is directly underneath the operating system, offering better performance and efficiency but requiring specific hardware.
• Hypervisor Type 2 (hosted hypervisor): Virtualization software runs on top of the host operating system, making it more versatile, but impacting overall performance.
• Containers: Lightweight, isolated environments that run applications with their dependencies within a single process.

Docker Advantages

• Portability: Docker allows easy movement of applications between different environments.
• Isolation: Applications in Docker containers are isolated from other containers and the host operating system.
• Resource Efficiency: Docker containers share the host operating system kernel, resulting in lower resource consumption compared to virtual machines.
• Deployment Speed: Docker images can be deployed quickly, leading to faster application development and deployment cycles.

Docker Concepts

• Images: Templates that define a container's environment, including the application, its dependencies and other configurations. These images contain instructions for constructing containers.
• Containers: Runnable instances of Docker images; isolated runtime environments for applications.
• Registries: Secure repositories that store docker images, making them shareable and downloadable.

Docker Operations

• docker build: Used to create container images from instructions in a Dockerfile.
• docker pull: Downloads images from a registry, e.g., Docker Hub.
• docker run: Executes a container based on an existing image.
• docker ps: Lists running containers.
• docker kill/stop: Terminates a container.
• docker image: Manages container images, like listing or checking for images.

Docker Usage

• Command-line interface: Using commands like docker run, docker build, docker pull.
• Graphical interfaces: Examples include Docker Desktop or Portainer.io.

This quiz provides an overview of Docker, its structure, and its key advantages. Learn about the types of hypervisors, the concept of containers, and how Docker enhances application portability and resource efficiency.