Docker allows for the deployment of applications inside lightweight Linux containers. It uses Linux kernel features like namespaces and cgroups to isolate containers and share resources efficiently. Docker images are read-only templates that stack together using a union filesystem like overlayfs. This approach allows for fast deployment of containers from images that can be committed, shared, and versioned using Dockerfiles and a registry. Docker simplifies deployment across teams and environments while improving security and portability of applications.

1. Docker
Please contain your excitement
Docker
Please contain your excitement
John Leach
john@brightbox.com
@johnleach
Brightbox Cloud
www.brightbox.com

5. VirtualisationVirtualisation

6. DockerDocker

7. Linux NamespacesLinux Namespaces

8. unshare commandunshare command

9. Mount NamespaceMount Namespace

10. Network NamespaceNetwork Namespace

11. Process NamespaceProcess Namespace

12. UTS NamespaceUTS Namespace

13. User NamespaceUser Namespace

14. IPC NamespaceIPC Namespace

15. cgroupscgroups

16. Namepaces + cgroupsNamepaces + cgroups
How can we bring this all together?

17. LXC – Linux ContainersLXC – Linux Containers

18. Docker vs. LXCDocker vs. LXC
What makes Docker different?

19. DockerDocker

20. Docker imagesDocker images

21. Docker Images: LayersDocker Images: Layers
511136ea3c5a
f3c84ac3a053
a1a958a24818
9fec74352904
d0955f21bf24
Container layer (a65ee08f6)
overlayfs
Hard linked together

22. Container layersContainer layers

23. docker commitdocker commit

24. docker commitdocker commit

25. docker savedocker save

26. DockerfileDockerfile
FROM ubuntu
RUN apt-get update -qqy
RUN apt-get install -qqy cowsay
ENV MESSAGE “nothing to say”
CMD sh -c "/usr/games/cowsay $MESSAGE"

29. docker pushdocker push

30. docker pulldocker pull

31. mysql imagemysql image

32. NetworkingNetworking

33. Service discoveryService discovery

34. Persistent storage with VolumesPersistent storage with Volumes

35. The unit of deploymentThe unit of deployment

36. The Future of DockerThe Future of Docker

37. Docker
Please contain your excitement
Docker
Please contain your excitement
John Leach
john@brightbox.com
@johnleach
Brightbox Cloud
www.brightbox.com