Techsessie Docker

2015

17 september 2015

Presentatie Daniël Palstra

Let’s talk Docker..

@dpalstra

Daniël Palstra

Docker… wut?!

Why shouldyoucare

It’s pretty much the best

thing for cloud computing

since the movement from

bare metal

to virtual machines

Ho Ming Li (DockerCon 2014 attendant)

Docker aims to reduce the

cycle time between

code being written

and code being tested,

deployed, and used.

James Turnbull (author of The Docker Book)

Docker is one of those

technologies that, without any

great fuss and without

anyone noticing, is now

everywhere. […]

I wouldn’t call Docker a

“Swiss Army Knife”

— it has so many more uses

than that.

Dr Mike Norman (Cloud Services Architect @

JP Morgan)

Dev to Ops the old way..

Dev to Ops the new way!

#whoami

• Daniël Palstra

• Docker Trainer @ Amazic

• DevOps consultant & engineer(self employed)

• Middleware & cloud

technologies

• 10+ yrs IT experience

• @dpalstra

DevOps means giving a shit

about your job enough

to want to learn all the parts

and not just your little world.

John E. Vincent (blog.lusis.org)

10,000

feet

WAY UP

The real value of Docker is not

technology,

it’s getting people to agree on

something.

Solomon Hykes (Founder of Docker)

Containers &

Images

NEXT UP

Almost everything in Google

runs in a container.

Brian Dorsey (Google Cloud)

What is Container

Virtualisation?• Alternative to “traditional” virtualisation on Hypervisors such

as VMWare

• No guest operating system (or booting) required for

containers

• Virtualisation layer runs as an application inside the host

OS

• Sandboxed execution environment

• Lightweight, high performance (especially on bare metal

hardware)

Where does Docker fit

in?• Built on top of Linux container technology (LXC, AUFS)

• Provides tools to build, run, share and version “images”

• Handles communication between running “containers”

(network, fs)

• Docker containers run practically everywhere

• Extremely reproducible; you could start from scratch

every time!

Docker containers

Images versus

Containers• Docker images consist of one or more read-only layered

file-systems

• The bottom layer is called the base image (Linux kernel,

e.g. Red Hat)

• A Dockerfile is the equivalent of a build file to create an

image

• Docker containers are the running, stateful instances of

images

• Modified containers can also be committed back to images

Docker build

demo

NEXT UP

FROM jboss/wildfly

MAINTAINER Bastiaan Schaap <http://github.com/siteminds>

RUN /opt/jboss/wildfly/bin/add-user.sh --silent admin admin

ADD sample.war /opt/jboss/wildfly/standalone/deployments/

EXPOSE 8080

EXPOSE 9990

Sample Dockerfile

VolumesWhere did my data go?

Volumes and mounting• Share directories and files with

• Docker Containers

• Docker Hosts

• Define volumes

• Runtime (docker run -v)

• Build time (VOLUME /path/to/my/directory)

• Ambassador containers

• Pluggable!

LinkingGlueing containers together

Container linking

• Container Port mapping

• Docker linking system

• Name containers and provide link

docker run --name web --link db:mongodb -d -p 8080:80

nginx

Logging &

inspection

What’s happening in my

env?

Logging

• Multiple log driver support

• Container != Host logging

docker logs -f nostalgic_morse

docker inspect -f '{{ .NetworkSettings.IPAddress }}' nostalgic_morse

172.17.0.5

Docker HubWhere to get my images from?

• Cloud-based registry

service

• Official images

• User defined images

• On premis solution

available

• Connect with Github

Docker Hub

Docker

Toolbox

Cool! How do I get started?

• Docker Client

• Docker Machine

• Docker Compose (Mac

only)

• Docker Kitematic

• VirtualBox

Docker Toolbox

Docker Machine

• Simplify creation and configuration of

Docker Hosts (inc security)

• Boot2docker >> docker-machine

• Multiple providers:

…

$ docker-machine ls

NAME ACTIVE DRIVER STATE URL SWARM

default * virtualbox Running tcp://192.168.99.100:2376

swarm-01 digitalocean Running

swarm-02 digitalocean Running

Docker Compose

• Define and run multi container applications

• Complete application lifecycle management

• Orchestration tool combined with Machine and Swarm

web:

build: .

ports:

- "5000:5000"

volumes:

- .:/code

links:

- redis

redis:

image: redis

Orchestration &

Clustering

Docker Swarm

• Docker Host clustering

• Smart Container Scheduling

• Docker-Machine &

Docker compose Integration

• Pluggable Node Discovery

• Container communication over multiple hosts (experimental)

3th party tooling

ConclusionFINALLY..

Pros

• Standardized way of getting code from development to production

• Easy to use DevOps workflow

• Fast container startup

• Isolation of processes and their configuration

• Amazing growth in functionality

Cons

• Very easy to do, can be very hard to do right

• Networking can be difficult

• Ecosystem evolving (rapidly)

• Which orchestration tools/platforms/frameworks to use

Questions?THANK YOU

@dpalstra

daniel@amazic.com

Demo time!