This document provides an overview of Docker, including an analogy to describe containers, examples of how Docker can speed up development and deployment by packaging applications into containers, and a breakdown of key Docker concepts and commands like Dockerfile, docker build, docker run, docker images, and docker containers. It demonstrates how to build and run a simple nginx container, and discusses how Docker can help with continuous integration/deployment by allowing applications to be packaged and run consistently across different environments.

1. DevOps #S01E01
Docker overview

2. (useful) Analogy

3. From industry to IT

4. From industry to IT

5. From industry to IT

6. Package it!

7. Containers technology

8. Mature technology

9. Success story
– Speed: Boots in seconds
– Footprint: 100-1000 containers by machine
– Public registry: hundreds of useful containers
– Build and versionning processes: git flavor

10. VM vs Container

11. Anatomy

12. Build once, run anywhere*

13. Docker lifecycle
– A build produces an immuable image
– A container is an instance of the image

14. Dockerfile
– Describe the way to build your container
– Imperative not Declarative
– A mix of RUN, ADD commands

15. Dockerfile, nginx
FROM ubuntu
MAINTAINER your@email.com
# Install deps
RUN sudo apt-get update && sudo apt-get install -y nginx
[ . . . ]
# Add some static files
ADD my-static-dir /usr/share/nginx/html/
# Expose ports
EXPOSE 80 443
# Run the server
CMD nginx

16. First build

17. Docker run
– Create an instance of an image: container
– Start the container with a specific config
– Run runs a process and stops when it dies

18. Docker run
docker run <mode> <ports> <volume> <image> <cmd>

19. First run

20. Docker run
Daemon VS Interactive
-it: foreground, attach a tty and STDIN
-d: damonized container

21. Docker run
Ports mapping
-p <host>:<guest> // -p 8080:80 (map 8080 to 80)
-p <ip>:<host>:<guest> // for listening interface
All rules are iptables

22. Docker run
Volume mount points
-v <host_directory>:<target>

23. Docker run
Override default usage
/bin/bash: useful for debugging purposes
/bootsrap.sh --with-my-config =value
etc.

24. Docker run
Other (very) cool stuff
--net: DHCP/Host/Bridge
--link + name:
-e VAR=VAL: set env variables inside the container
.dockerignore (like .gitignore)

25. Docker run
Other (very) cool stuff (cont’d)
--privileged and –CAP: for security
--user: first owner
--cpuset: assign vcore to the container
See https://docs.docker.com/reference/run/#user

26. Demo

27. Docker lifecycle

28. CI, big picture

29. Support us!
Guillaume Polaert / @gpolaert
https://registry.hub.docker.com/u/ingensi