Docker Introduction
- 1. Introduction to Docker Containerization
- 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.
- 6. Creating the first Docker 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 and containers ● 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 detached mode ● 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 mode is 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 real application ● 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 is a 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 is a 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 up the services with $ docker-compose up ● Describe you services with docker-compose.yml ● Three web applications ● One nginx reverse proxy