Docker 101

From Development to Production and back

by Dmitri Pisarev / @dimaip

• Work and study in SFI.ru — first independant Christian Theological University in Russia
• Worked with TYPO3 since 2006
• One year ago first installed Neos... And loved it!
• Neos contributor since then

What's Docker?

The Next Big Thing?

Extremly lightweight VM?

Almost. At least it feels like one

Virtual Machines

Containers

Way less fat here!

FreeBSD jails on steroids?

Official answer

Docker is an open platform for developing, shipping, and running (distributed) applications

What problems does it solve?

1. Setup development environments in minutes
2. Have identical environment in production and development
3. Freedom to try new things without worrying about infrastructure

Key terms

• Container
• Image
• Image registry

Container

Container is an isolated and secure application platform, that holds everything that is needed for an application to run

Image

A Docker image is a read-only template used to create Docker containers

Image registry

Docker registries hold images.
The public Docker registry is called Docker Hub.

Architecture overview

Join the session now!

Stuff to expect:

• Install the thing
• Learn the basic usage
• Going to production
• And much more!

...where we left off

Agenda:

• Installation
• Managing data in containers
• Orchestration with Docker Compose
• Going to production

Getting started

Installation on Linux

wget -qO- https://get.docker.com/ | sh

Installation on Mac/Windows

• You need boot2docker VM
• Use OSX or Windows installer
• Try without host volumes first
• Be ready for trouble!

Create and start a container

docker run -i -t busybox sh

Managing data in containers

Layered filesystem

Data volumes

/var/lib/docker/volumes/fe04a94dfaad3d9efa99c81bd79a42b383b55171...

Data-only containers

Docker Compose

Data-only containers in practice

dbdata:
  image: busybox:latest
  command: echo dbdata
  volumes:
    - /var/lib/mysql

webdata:
  image: busybox:latest
  command: echo webdata
  volumes:
    - data:/data
      

Good old mySQL database

db:
  image: million12/mariadb:latest
  ports:
    - 3306
  volumes_from:
    - dbdata
  environment:
    MARIADB_PASS: pass
  restart: always
    

Web container with Neos demo site

web:
  image: million12/typo3-neos
  ports:
    - '80'
  links:
    - db:db
  volumes_from:
    - webdata
  environment:
    VIRTUAL_HOST: 'neosm.dev,dev.neosm.dev'
    T3APP_NAME: 'neosm.dev'
    T3APP_NEOS_SITE_PACKAGE: 'TYPO3.NeosDemoTypo3Org'
  restart: always
    

SSH container

ssh:
  image: million12/php-app-ssh
  ports:
    - '22'
  links:
    - db:db
    - web:web
  volumes_from:
    - webdata
    - dbdata
  environment:
    IMPORT_GITHUB_PUB_KEYS: dimaip
  restart: always
  

Redis in a few lines of code

redis:
  image: redis
					

To Production!

Nginx reverse proxy

docker-gen

Generate any sorts of configs based on data from running docker containers

• Reverse-proxy configs
• SSH config file
• Whatever you like!

Deploying containers

1. Merge change to master branch on Github
2. Image is automatically rebuilt on Docker Hub
3. Pull new image, run it in parallel with the old one, test
4. Redirect traffic to new container, stop the old one
5. Rollback if things go wrong

Great for big infrastructure changes,
but slow for code-only deploys

Hybrid deploy