Why would you want to use Docker and containers, and how people already

1. Why to Docker?

2. Karthik Gaekwad
Senior Engineer
Previous
11 years of building software for large
and small enterprises

3. Karthik Gaekwad
•Lead Organizer Devopsdays Austin
•Lead Organizer CloudAustin
•Agile Conference 2014/15:
•DevOps track reviewer

4. Objectives
•What is Docker
•Why is it so popular
•How are enterprises using it today
•Questions!

5. Quick Note:
Feel free to ask any questions you may have
in the question box. If I can’t answer it during
the presentation, I’ll write a blog with
answers on stackengine.com

6. What is Docker?
Open source platform for developers and
sysadmins to build, ship and run distributed
applications anywhere.

7. Docker Ecosystem
•Docker Engine
•Runtime and packaging tool
•Installed on hosts that run Docker
•Docker Hub
•Cloud Service for storing and sharing
applications
•Saving images (public/private)

8. Docker Features
•Portability
•Standardized Environments
•Rapid scale-up/scale-down
•Ability to build a continuous delivery (CD)
pipeline
•Dependency management

10. Portability
•Idea of writing once and running anywhere.
•As long as your application is Dockerized, you
can run it anywhere that has the Docker
Engine installed.
•Easy to change from 1 host to another.
•Flexibility to change underlying
infrastructure/operating systems etc.
•Change from 1 cloud provider to another.

12. Standardized Environments
• Coding environments can be made consistent from
development ->staging->QA->production.
• Per environment configurations are fed in the same
way to each container which reduces configuration
issues.
• Time spent debugging environmental issues is
reduced drastically.
• Developers understand the production environment
better, which leads to better code quality.

13. No more this:

15. Scaling
•Containers take seconds to deploy.
•Scale up and down your infrastructure is a
lot faster than traditional configuration
management tools.

17. Continuous Delivery/Deployment
• Docker API’s and Docker Hub make it easy to build a
deployment pipeline.
• After successful builds, a CI system can build and push a
Docker image to the Hub/private Docker repo.
• Deploy new containers to desired environment on a periodic
basis/trigger webhooks to deploy.
• Detailed example later..

19. Minimize Dependency Hell
•Dependency hell happens when:
•2 running Java or Ruby applications that depend on
different versions of the same library…..
•How Docker can help:
•Isolate each application (along with it’s
dependencies) so that they can be loaded in their
own container.
•1 container for 1 application or service (micro
service architecture)

21. Standardized Environments
• Starting point for most organizations to use Docker.
• Take existing (or new) applications, containerize them, run
them the same way on dev/stage/production.
• Examples on Docker.com: Orbitz, Uber
• @StackEngine:
• All our infrastructure run in containers.
• Every code push builds a new container for the application.
• All environments uses the same command to run the application:
• sudo docker run -d -p 7777:7777 -e SE_DB=‘db_val’
stackengine/admin

22. Pipelines
• Most common usecase of how people use Docker today.
• Examples on Docker.com: Business Insider, Spotify, Yelp
• @StackEngine:
• Code is commit to github; triggers a build with CircleCI.
• Successful build results in a built container that is deployed to a
private registry.
• Successful push to registry triggers a webhook to the StackEngine
product.
• StackEngine redeploys new container to production.
• 4 minute turnaround from commit->running in production.

23. Multi tenancy applications
•Single Tenant application-> Multi tenant
application by launching multiple instances
of the same application in different
containers.
•http://flux7.com/docker/

24. Other use cases
•Running a PaaS
•Running entire datacenters using Docker.
•EngineYard/Yandex/Baidu are great examples
of this.
•Hosting Legacy Applications
•Containerizing hard to run applications is
becoming a frequent usecase.

25. Docker in Production?
•Great blog post summarizing current
challenges: http://sirupsen.com/production-
docker/
•Already made huge strides in
networking/log management.
•Recommendation:
•Start small, learn, adapt, expand.

26. Players in the space

28. Resources for learning Docker:
•Docker 101 (@behemphi):
http://stackengine.com/docker-101-01-docker-
development-environments/
•Docker Tutorials by John Willis:
https://blog.docker.com/author/john-willis/
•The Docker Book- James Turnbull