Docker Introduction

Docker Introduction

• 1.
  Introduction to DockerContainerization
• 2.
  What is Docker? ● System level virtualisation technology. ● Produces Lightweight virtual machines. ● Isolate processes from the host environment (fs isolation, net isolation, id isolation).
• 3.
  Docker VS VMs? Docker Virtual Machine
• 4.
  Why Docker ? ●Package applications and their dependencies in one portable abstract unit. ● Shortens deployment time and effort. ● Ease application scaling on a very large compute domain. ● New perspectives : Micro-services based architecture.
• 5.
  Docker Ecosystem
• 6.
  Creating the firstDocker Container ● Pull the Ubuntu image from the registry. $ docker image pull ubuntu ● Start a container based on the Ubuntu image $ docker container run -it –-name ubuntu ubuntu /bin/sh
• 7.
  Listing images andcontainers ● List images $ docker images $ docker image ls ● List running containers $ docker ps $ docker container ls ● List all containers $ docker ps -a $ docker container ls -a
• 8.
  Start in detachedmode ● Add -d option to docker run $ docker run -dit –-name ubuntu ubuntu /bin/sh ● To leave container without exiting it CTRL + P + Q ● To connect the terminal to the detached container $ docker attach {id} | {NAME}
• 9.
  Networking ● Default modeis bridge : All containers and host are connected to a virtual switch in the same subnet 172.17.0.0/16 ● List network drivers $ docker network ls ● Show information of a network driver $ docker network inspect bridge
• 10.
  Deploy a realapplication ● We will deploy Flask application ● Start from a base image of Ubuntu with Python and Flask installed ● Create a new image and add our custom application.
• 11.
  Dockerfile ● It isa text file that contains a sequence of instruction to build an image from an existing one. ● Build the image with $ docker build -t <tag> ● Launch the container $ docker run -d –-name app <tag>
• 12.
  Micro-services and scaling ●What if we have multiple services and we want to automate the process of deployment ? ● Or What if we want to scale up our application with ease ?
• 13.
  Docker-compose ● Docker-compose isa mean to describe the deployment of multiple containers/services with one single yml file. ● It eases the scaling up of an application.
• 14.
  Docker-compose
• 15.
  Docker-compose ● Bring upthe services with $ docker-compose up ● Describe you services with docker-compose.yml ● Three web applications ● One nginx reverse proxy