This document discusses Docker, a tool for creating and running containerized applications. It explains that Docker provides simple deployment of applications by allowing quick starting of images with the same speed as starting programs directly. It also enables central repositories for images, repeatable testing environments, and easier scaling of applications across multiple servers. Some potential issues discussed are that Docker only supports Linux containers currently, adds more moving parts than traditional virtualization, and requires learning something new. The document demonstrates installing and using Docker through examples and recommends best practices.

1. for full stack
development

2. or
Vagrant is so last year
Why aren't you using
docker yet?

3. Who am I
Tim Haak
@tim_haak
tim@haak.co.uk
https://github.com/timhaak
phpsa2014_docker_talk
Company: Afrihost
What I do:
Bit of everything from server to frontend

4. Warning
This presentation may contain pictures of cats!!

5. First what is docker?

6. In simple terms it’s
a easy way to
create
containerized Linux
based applications

7. Without the
overhead of
virtualization

8. Why is everyone talking about it

9. It solves a couple basic problems

10. Simple deployment
• Matter of seconds to start and image
– Same speed as starting the programs inside the
image
• Central repository for images
– Similar to github
– Public, Private and self hosted available

11. Simple deployment
• Can start multiple copies quickly
• Simple rollback
– With in reason
• Oh and versioning

12. Repeatability
• You can test the exact image that you will run on the
server
• Allows for simpler testing
• There is no difference between testing and dev.
• It should remove but it worked on my pc excuse
• Documented install steps
– Stops the I can’t remember what’s installed on
this server

13. Simpler to scale
• You can simply move multiple containers on
one server to many
• If you follow best practices
– This should be obvious but we all know how it
goes
• Allows you to run multiple flavors and versions
of Linux on one server.

14. Ok but what are the problems?

15. Only for Linux
• Personally don’t have a problem with this 

16. More moving parts
• Can add complication compared to running a
single server
• But more than makes up for it as you scale
• Not as simple as just logging into a server to
check how its working

17. Not for everything
• Would not use it for larger critical DB’s
– You generally want to be a close to the metal as
possible
• Though great for you local development DB
– Though needs to be smaller than 10G
– There are workarounds for this.

18. Biggest problem
• It works slightly differently and people will
have to learn something new.
• Worth it once all the pieces are in place.

19. Demo Time

20. Install Docker
• Get Ubuntu 12.04/14.04
– Or flavor of choice
• Follow how to on dockers site
– https://docs.docker.com/
• Done
– Very good documentation

21. But I'm on Mac or Windows
• Vagrant
– http://www.vagrantup.com/
• Boot2Docker
– https://github.com/boot2docker

22. But I thought you said vagrant was
so last year

23. I lied 

24. Its great to get a basic system up
and running.
But that’s where you should stop.

25. Etcd
• Simple, curl-able API (HTTP + JSON)
• Optional SSL client cert authentication
• Benchmarked 1000s of writes/s per instance
• Properly distributed using Raft protocol

26. Etcd
• Keys support TTL
• Atomic test and set
• Easily listen for changes to a prefix via HTTP
long-polling

27. Initial System

28. Once container has started

29. Some tips
• Separate your programs
• Don't repeat step build a base image
• Store persistent data externally
• Build containers to be thrown away
• Put all the steps in the Docker file
• Use env variables

30. Questions