Docker

What is Docker ?

Docker is the world’s leading software container platform Docker makes the process of application deployment very easy and efficient and resolves a lot of issues related to deploying applications Docker is a tool designed to make it easier to deploy and run applications by using containers Docker gives you a standard way of packaging your application with all its dependencies in a container Containers allow a developer to package up an application with all of the parts it needs, such as libraries and other dependencies, and ship it all out as one package.

Understand a general workflow of docker

Difference between virtualization and containerization

Understand docker client server architecture

Understand:

Docker file

Docker images

Docker Containers

Docker Hub / Registry

Docker client

Docker server / daemon

Docker engine

Benefits of using Docker

Build app only once

No worries that the application will not perform the same way it did on testing environment

Portability

Version Control

Isolation

Productivity

Docker simplifies DevOps

Prerequisite

OS should be 64 bit

Linux kernel ver 3.10 or greater

command to check :

uname -r

STEP 1 - Connect to Linux system

STEP 2 - Install DOCKER

sudo yum -y update

sudo yum install -y docker

Docker

docker --version

STEP 3 - start DOCKER

sudo service docker start

sudo usermod -a -G docker "user"

docker info docker run hello-world : to run hello-world image

docker images : to get list of images present locally

docker ps : to get list of running containers

docker ps -a . : to get list of all containers

STEP 4 - stop DOCKER

sudo service docker stop

uninstall DOCKER

sudo yum remove docker

Docker Basic Commands

Step by Step for Beginners

Basic :

docker version

: docker -v

: docker info :

docker --help

: docker login

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Images

: docker images

: docker pull

: docker rmi

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Containers

: docker ps

: docker run

: docker start

: docker stop

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System

: docker stats

: docker system df

: docker system prune

References :

https://hub.docker.com/

https://docs.docker.com/engine/refere...

Dangling Images

A dangling image is one that is not tagged and is not referenced by any container.

Today we will learn :

1. What are images

2. How to pull image

3. How to run a container using an image

4. Basic Commands

TIPS & TRICKS

What are Images

Docker Images are templates used to create Docker containers

Container is a running instance of image

Where are Images Stored Registries (e.g. docker hub)

Can be stored locally or remote

: docker images --help

: docker pull image

: docker images

: docker images -q

: docker images -f “dangling=false”

: docker images -f “dangling=false” -q

: docker run image

: docker rmi image

: docker rmi -f image

: docker inspect

: docker history imageName

References:

https://hub.docker.com/_/ubuntu/

https://docs.docker.com/engine/refere...

Today we will learn :

1. What are Containers

2. How to create Containers

3. How to start / stop Containers

4. Basic Commands

TIPS & TRICKS

What are Containers:

Containers are running instances of Docker Images

COMMANDS

: docker ps

: docker run ImageName

: docker start ContainerName/ID

: docker stop ContainerName/ID

: docker pause ContainerName/ID

: docker unpause ContainerName/ID

: docker top ContainerName/ID

: docker stats ContainerName/ID

: docker attach ContainerName/ID

: docker kill ContainerName/ID

: docker rm ContainerName/ID

: docker history ImageName/ID

References:

https://www.google.co.in/search?rlz=1...

https://docs.docker.com/engine/refere...

Notes

A container image is a lightweight, stand-alone, executable package of a piece of software that includes everything needed to run it:

code, runtime, system tools, system libraries, settings.

Features of Containers:

Are lightweight

Fewer resources are used

Booting of containers is very fast

Can start, stop, kill, remove containers easily and quickly

Operating System resources can be shared within Docker

Containers run on the same machine sharing the same Operating system Kernel, this makes it faster

You can use the command

docker container create

to create a container in stopped state