Docker is a tool that allows users to easily create and manage lightweight containers. It has four main components: Dockerfile for building images, a command line tool, an API, and a registry. At Gilt, Docker is used to build images for every version of applications and deploy them by pulling images to hosts and running containers. Docker provides benefits like lightweight runtimes, application isolation, stable environments, and repeatability.

1. Exploring Docker
at Gilt

2. A few concepts first...
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cgroups
namespaces
chroot
containers
lxc
aufs
Containers are not VMs

3. Ok… so, what is docker?
● An easy way to create containers
○ Portable
○ Self-sufficient
● Uses lxc and aufs*
● Written in go

4. Ok… so, what is docker?
● 4 main components:
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Dockerfile (image building tool)
A command line tool
A service api
A registry

5. Docker - dockerfile
# cat Dockerfile
FROM ubuntu:13.04
RUN apt-get install python-software-properties
RUN add-apt-repository ppa:duh/golang
RUN apt-get update
RUN apt-get install golang
ADD . /lalala
EXPOSE 5000
CMD cd /lalala && go run lalala.go
# docker build -t lalala:1.0.0 .

6. Docker - command line tool
#
#
#
#
docker
docker
docker
docker
run lalala:1.0.0
ps
kill 6465778d29e4
logs 6465778d29e4

7. Docker - service api
# docker run ubuntu echo “lalala”
POST /images/create
POST /containers/create
POST /containers/{id}/start
# docker ps
GET /containers/json

8. Docker - registry
● There is a public and a private option
● Public: index.docker.io
● It has an API

9. How we use docker @ gilt?
● We build images for every version of every
application.
● We deploy by pulling images to the selected
hosts and run containers.

10. Why we like Docker?
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Lightweight runtime environments
Application isolation
Stable runtime environments
Repeatability

11. Questions???
Jonathan Leibiusky
(@xetorthio)
ionathan@gmail.com
Thanks!!!