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
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 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.
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.
Step 3: Now save and share your image
You must be signed in to Docker Hub to share your image.
Save and share your image on Docker Hub to enable other users to easily download and run the image on any destination machine.
docker push /docker101tutorial
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.
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