Docker Classroom Series – Sep/25/2019

Lab Setup

• Windows:

  • Visual Studio Code:

    • Chocolatey: As Referred here

    • Choco command :

    • Directly as referred here

• Mac or Linux:

  • Visual Studio Code: Refer here
  • Linux Specific: Refer here
  • Mac: Refer here

Scenario

• I need tomcat 8:
• Approach in VM’s:
  • Create a linux machine
  • Login to the linux machine
  • Execute sudo apt-get update && sudo apt-get install tomcat8 -y
• Approach in Docker:
  • Lets use Docker playground. Refer here
  • Try these commands

  docker run -d -p 8080:8080 tomcat:8
  docker run -d -p 8081:8080 tomcat:9
  docker run -d -p 8082:8080 tomcat:9
  

What is happending during Docker RUN

• docker client forwards run request with image name to docker daemon
• Docker Daemon checks for image in local images
• If it is not found it tries to download from registry. (Default registry is Dockerhub.com)
• Then Daemon creates container from image.

Importance

• We must know how to create Docker Images for the applications which your team is building

How to create Images?

• Standard Approach: Create images by writing Dockerfile
• Clone Approach: Manually Create container & then copy image

Four terms of Importance

• Docker Image
• Docker Container
• Docker Client
• Docker Daemon