This document discusses why Docker is useful for creating consistent and isolated development environments. Docker allows independence from the host machine by providing a clean environment to test projects. It can be used to build environments for specific projects, avoiding issues caused by differences in local machines ("works on my machine" problem). Docker images can also be used as test environments by pulling pre-built databases and apps. The document recommends Docker for running legacy projects in a consistent way and producing applications that can run anywhere Docker is supported.

1. Why?
Adam Štipák | @new_POPE | adam.stipak@gmail.com

2. Why use it?
● Virtual environment
● Independence
● Clean host machine
● Test environment for experiments
● Build for project (“works on my machine problem”)

3. Virtual environment
● docker pull …
● docker run …

4. Independence
Hands up who are using linux?

5. Independence
Docker runs everywhere

6. Clean host machine
Only one dependency

7. Test environment
● docker pull mysql
● docker pull wordpress:<tag>
○ <4.7 | 4.7.4-fpm | 4.7.4-php7.1-apache | ?latest?>
● docker run -d --name mysql -e MYSQL_ROOT_PASSWORD=password mysql
● docker run --link mysql:mysql -p 9000:80 wordpress

8. Build for project
● git clone …
● docker build ...
● docker run ...

9. Build for project - pros & cons
● fast start
● easy to use
● consistent environment for
○ team
○ project
● no need Vagrant
● build for Linux
● new tool

10. Build for project
Docker compose
- is a tool for defining and running
multi-container Docker applications

11. Run in production
● end of classic hosting services
● Amazon EC2 Container Service
● Google Container Service
● Digital Ocean
● Microsoft Azure
● ...

12. Legacy project
● check requirements (php, mysql, …)
● setup image for project
● build
● run
Win!

13. Recap - why use Docker?
● consistent environment
● runs different project on one server (less costs)
● exotic setup for projects

14. BTW, we’are using Docker on daily basis
● Catch me to talk about Docker or how to switch your project to Docker
● Come to one of our Docker trainings
rekurzia.sk # docker

15. Thank you
questions?
Adam Štipák | @new_POPE | adam@rekurzia.sk