Learning Docker

Topics Covered

1. Understanding Images v/s Containers

2. Running Ubuntu Image in Container

3. Multiple Containers

4. Port Mappings

5. Environment Variables

6. Dockerization of Node.js Application

   1. Dockerfile

   2. Caching Layers

   3. Publishing to Hub

7. Docker Compose

   1. Services

   2. Port Mapping

   3. Env Variables

Part 2

1. Docker Networking

   1. Bridge

   2. Host

2. Volume Mounting

3. Efficient Caching in Layers

4. Docker Multi-Stage Builds

Some Basic Docker Commands :

1. List all active containers:

   docker container ls

2. List all active and inactive containers:

   docker container -a

3. Start a container:

   docker start container_name

4. Stop a container:

   docker stop container_name

5. List directories inside a container and exit:

   docker exec container_name ls

6. Access a container's shell interactively (without exiting):

   docker exec -it container_name bash

7. List all locally available Docker images:

   docker images or docker image ls

8. Run a Docker container interactively, expose a specific port, and set environment variables:

   docker run -it -p 1025:1025 -e key=val mailhog/mailhog

9. Build a Docker image from a specified directory and assign a name:

   docker build -t image_name directory_path

   Example:

   docker build -t my_app .

10. Log in to your Docker Hub (or other registry) account:

    docker login

11. Create and start containers

    docker compose up <--attach or --detach > & docker compose down

Docker Networking

1. Docker Networking

   • Host : uses Host machines network

     docker run -it --name my_container --network=Host Image_Name

   • Bridge : Establish Bridge between Host machine and docker

     docker run -it --name my_container --network=Bridge Image_Name

   • none : No internet

     docker run -it --name my_container --network=none Image_Name

2. Create Custom Docker Network

   docker network create -d bridge mynet

   • containers which uses same network can communicate with each other

3. use docker network ls to List down all available networks,

4. use docker network inspect <network_name> to see which cotainers are using the same network.

Volume Mapping

1. to Create volume :

   docker run -it -v <host_file_path>:<container_file_path>

   for example :

   docker run -it -v /Users/HP/Desktop/test-folder:/home/test ubuntu