Sides from my Jfokus 2015 talk. # Abstract Does your application deployment rely on an unhealthy amount of shell scripting glue code? Start encapsulating your application and its runtime environment in Docker containers. This talk will give you a brief introduction to the concepts behind Docker and a handful of tips to get you started on the exciting journey towards a more robust and reliable application deployment. By the end of the talk you will have learned how to build and deploy Docker images, how to let your containers talk to each other and why the JVM and Docker are a perfect match.

1. Docker & JVM
A Perfect Match
Matthias Grüter // @mattgruter
Jfokus 2015

2. Image Credit: Tim Kirman

3. Image Credit: Tim Kirman

4. Your Toastmaster
Matthias Grüter

6. Containers
Credit: containersfirst.com.au

7. VM
Container

8. Shipping Containers
Credit: danielpivnick

9. Build, Ship and Run
Any App, Anywhere

10. Let's create some
containers!

11. Container Networking

12. Ports to the outside world
docker run ­p 9000:8080 ...
Format: [hostPort]:[containerPort]

13. Container Linking
1. Database container "redis1"
docker run ­­name redis1 redis
2. Application container "myapp" (wants DB backend)
docker run ­­link redis1:db myapp
Format: ­­link [containerName]:[alias]

14. Docker Images
Container Blueprints
Source: homeinabox.blogspot.se

15. Layered Filesystems

16. Sharing Images

17. Creating Images

18. Example: Jenkins
FROM debian:jessie
# install java
RUN apt­get update && apt­get install ­y openjdk­7­jre
# install jenkins
ADD http://mirrors.jenkins­ci.org/war/1.597/jenkins.war /
ENV JENKINS_HOME /jenkins
WORKDIR /jenkins
EXPOSE 8080
CMD ["java", "­jar", "/jenkins.war"]

19. Example: Jenkins
Build:
docker build ­­tag jenkins .
Run:
docker run ­p 8080:8080 jenkins

20. Data Volumes
Expose:
docker run ­v /data ­­name db redis
Access:
docker run ­­volumes­from=db rsync ­r /data/ remote:/backup
Credit: Tony Cole

21. A Perfect Match

22. Image credit: snorgtees.com

23. Docker and the JVM
Encapsulation (app + libs)
Memory management
Portability
Encapsulation (runtime)
Isolation & Containment
Portability

24. Docker and the JVM
Encapsulation
Sandboxing
Portability

25. Ecosystem
Docker API
Build system
Build/CI servers
Build repositories
...

26. Wedding Gift

27. Qubit‐Coins

28. The Grand Scheme

29. Webapp
Gradle
plugins {
id 'application'
}
mainClassName = 'se.qubit.webapp.Main'
group = 'mattgruter'
repositories { jcenter() }
dependencies { ... }

30. Webapp
Gradle & Docker
plugins {
id 'application'
id 'se.transmode.docker' version '1.3'
}
mainClassName = 'se.qubit.webapp.Main'
group = 'mattgruter'
repositories { jcenter() }
dependencies { ... }
distDocker.dockerfile {
EXPOSE 8080
}

31. Build
gradle distDocker
:‐)

32. Deploy
Wallet (Redis)
docker run ­d ­­name db redis
Miner
docker run ­d ­­link db:db mattgruter/qubit­miner
Webapp
docker run ­­link db:db ­p 8080:8080 mattgruter/qubit­webapp

33. Faster!
docker run ­d ­­link db:db mattgruter/qubit­miner
docker run ­d ­­link db:db mattgruter/qubit­miner
docker run ­d ­­link db:db mattgruter/qubit­miner
...

34. Image credit: Deep Impact

35. Your container is
NOT a VM
Stop treating it like one!

36. Corollary #1
Say no to sshd
use volumes, volumes, volumes
... and docker exec

37. Corollary #2
There can be only
one PID
Credit: imaginarywars.wordpress.com

38. Docker is a polyglot
tool!
So sorry, JVM!

39. Docker Hub
Automated Builds

40. Be Specific
Images are cheap, therefore ...
... build many small specific images.

41. Size Matters
Use small baseimages

42. Corollary
(e.g. apt‐get clean, multi‐line run)

43. Use the cache, Luke!
Move ADD & COPY to end of Dockerfile
(they invalidate the cache)

44. What does the future hold?
Credit: www.clipartbest.com/8balllogo

45. Image Credit: Tim Kirman

46. Credit: Solomon Hykes