What is a Docker?

Docker is a plateform which packages an application and all its dependencies togeter in the form of Containers. We can create , run and deploy application in conatiners.

What is a Container?

A container is a package of code, libraries and dependencies required for an application to run.

using docker container you can run your applications on premises, localhost, cloud or anywhere you want.

Docker makes it very easy to create ,deploy and run applications in the form of conatiners

Docker containerization tool used build your project, generate a Docker image and pushed/pulled to/from the docker hub This S/W is container runtime.

(

1 Clone
2 Build
3 Run
4 Share

)

Docker Image means all the instructions for Docker to perform to build container.

What problems docker solves?

Docker solve mismatched depenency

Docker workflow process

Docker file

Docker file contains set of predefined commands that are used to create a Docker image, Normally user used a CLI to call the command.

Docker Image

Template to create docker container.

Docker Container

Running instance of the docker image. conatiners hold entire package to run the application.

Install Docker

Install Docker.exe from offical website

Recommended: Please check System requirements first.

Installed

Docker signup

Docker dashboard after signin

Verify version

docker -v

Docker Engine

Docker server always run on Linux Virtual Machine.

Docker Hub

Docker Hub

Docker Hub Container Image Library to pull/push container images from central repository ie Docker Hub.

How do I run a Docker?

 docker run [docker_image] 

Step 1: Log in to Docker

Step 1: First, clone a repository

The Getting Started project is a simple GitHub repository which contains everything you need to build an image and run it as a container.

Clone the repository by running Git in a container.

docker run --name repo alpine/git clone \ https://github.com/docker/getting-started.git
docker cp repo:/git/getting-started/ .

You can also type the command directly in a command line interface.

Step 2: Now, build the image

A Docker image is a private file system just for your container. It provides all the files and code your container needs.

cd getting-started
docker build -t docker101tutorial .

Step 3: Now save and share your image

You must be signed in to Docker Hub to share your image.

Sign in here.

Save and share your image on Docker Hub to enable other users to easily download and run the image on any destination machine.

docker tag docker101tutorial /docker101tutorial

docker push /docker101tutorialDone

Step 4: Run your first container

Start a container based on the image you built in the previous step. Running a container launches your application with private resources, securely isolated from the rest of your machine.

docker run -d -p 80:80 \ --name docker-tutorial docker101tutorial

Step 4: Congrats

Container : Is a process which has a set/portion of physical resources.

Docker file: This is a simple plain text file contains all the stepwise info for running your software in a base container(ubentue 18 etc)

Image: The image is pulled from the docker hub.

Image = file system snapshot + startup command 

Docker file to Docker Image

Docker file -> Docker Client -> Docker Server ->Docker Image

Important command

docker -v docker pull