This document discusses Docker, an operating system-level virtualization tool. It compares Docker to virtual machines, noting that Docker allows setup to be done once and then shipped anywhere, unlike previous environments which required separate setup for each new machine. Docker creates an O(1) environment where development, testing, and production environments can all be identical, making it easier to maintain different projects and environments. The document provides examples of basic Docker commands like running containers from images and removing images.

1. Docker
An operating system-level virtualization — LXC

2. Compare to VMs

3. Before Docker — O(n)
DB, Server,
Cache
DB, Server,
CacheLean
DB, Server,
Cache
LB
Grow
DC #1
LB
Server n
DB n
Cache n
Scale
Dev Env Prod Env
Server1,
2, 3, 4
DB 1,2 Cache1, 2
DB, Server,
Cache
DC #2
LB
Server n
DB n
Cache n

4. • Setup required for each new box.
• Dev env and prod env are two different stores.
• Good luck with setup different dev env for different
projects.
• A lot of work for maintaining different environments.
• Bottleneck on testing and integration environments.
• Inflexible architecture setup.
Before Docker — O(n)

5. Docker — O(1)
DB
Lean
Grow
Scale
Dev Env Prod Env
Server
CacheLB
DB Server
CacheLB
DB Server
CacheLB
DB Server
CacheLB
DB Server
CacheLB
DB Server Server
Cache Server
Server
DB
Cache
LB
Server
DB
Cache
LB

6. • Setup once ship to anywhere.
• Dev env can have the identical setup as prod env.
• Easily switch dev env for different projects.
• More than one testing and integration environment
is simple, more than one version of environment is
what you really want.
• Inflexible architecture setup — Easily to try different
setups.
Docker — O(1)

7. Docker Commands
• docker images
• docker run -it ubuntu:14.04 /bin/bash
• docker rm <container id>
• docker rmi <image id>
• docker commit <container id> <image name>

8. Demo