Difficulty: Beginner
Estimated Time: 45min

Welcome in my first tutorial of Docker 101 - for beginners

In this set of scenarios, you will understand Docker and containers.

This first tutorial focuses on Docker Introduction :

  • Basics & commands lines
  • Container isolation
  • Container vs Host (PID and process)
  • Logs

play : at end of line, indicates you can click to execute command directly in terminal

played : at end of line, indicates you already clicked on it

copy : at end of line, press to copy text to clipboard

Thx for your participation

Feedbacks, comments and improvement are welcome !

Docker 101 - Introduction Overview for Beginners

Step 1 of 7

Container vs Virtual Machine

Docker is a greate tool to do container more easier than before. But what is a container ? Why use this ?

Container vs Virtual Machine

Virtual Machine has a guest OS with all bin, libs and stuff provides by Linux distribution (some linux distributions : CentOS, RedHat, Ubuntu, Fedora, Alpine, ...). It isolates vCPU / RAM guaranteed or shared to the virtual machine and do some isolation between the others virtuals machines on the host (a.k.a. VMWARE).

The minimum recommanded disk for CentOS is about 10 GB. The difficulty is when you have to migrate your development to production. You can't deploy a snapshot of your VM because your Dev environment isn't the same about your PROD.

Containers were born long before Docker but Docker give simple way and shorts commands to instantiate an isolation of process running inside the Container. Isolations are based on cgroup, Kernel capabilities, ...

Container are lighter than VM (CentOS is about 200 MB).

A container is an instantiation of an immutable image (deep explaination in a futur scenario). So Dev environment could easily send in Prod and both ar iso

Language & Comparison Container vs VM :

VM vs Container
v CPU isolation ~
v RAM isolation ~
10s -> 10 min Boot time ~1s
1 - 2 hours (without entreprise process) Build speed 10min
x ISO Prod v
10 GB Size 200 MB
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