DevOPS – Day 2Thursday, June 2th 2016

Questions since the previous workshop?

What is a container?

• Program executed in a limited kernel resources• Cgroups: CPU, Memory, Network, …• Namespace: Process, User, Filesystem, ...• Union file system: Filesystem

Virtual machine vs Container

Server

OS

Hypervisor

Guest OS

Libraries

App 1

Server

OS

Docker Engine

Guest OS Guest OS

Libraries Libraries

App 2 App 3

Libraries

App 1

Libraries Libraries

App 2 App 3

Containers for developers

• Micro service paradigm• Environment variables for application configuration

User

Contract

Support

Notification

Analytics

Invoice

Storage

Task

Containers for system engineers

• Blue/Green deployment• High level management• Security issues• Change all tools…

User

Load balancer

A version

B version

A version

B version

A version

B version

Web server Application Database

Docker

Very active project…You must read release notes and check technical details!

Docker softwares

DockerEngine

DockerMachine

DockerRegistry

DockerComposeKitematic

Docker Toolbox

Automate Docker provisioning

Desktop GUI for Docker

Multi-container orchestration tool

Run Docker container

Docker containers hosted registry

Helper to install Docker components on desktop

DockerCloud

Hosted service for building and

deploying containers

DockerSwarm

Host clustering and container

scheduling

Dockerfile

• Dockerfile is a document composed of various commands to assemble an image• Inherit from on a base image

DockerfileFROM ubuntu

MAINTAINER SvenDowideit@docker.com

RUN apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8RUN echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdgmain" > /etc/apt/sources.list.d/pgdg.listRUN apt-get update && apt-get install -y python-software-properties software-properties-common postgresql-9.3 postgresql-client-9.3 postgresql-contrib-9.3

USER postgres

RUN /etc/init.d/postgresqlstart &&\psql --command "CREATE USER docker WITH SUPERUSER PASSWORD 'docker';" &&\createdb -O docker docker

RUN echo "host all all 0.0.0.0/0 md5" >> /etc/postgresql/9.3/main/pg_hba.confRUN echo "listen_addresses='*'" >> /etc/postgresql/9.3/main/postgresql.conf

EXPOSE 5432

VOLUME ["/etc/postgresql", "/var/log/postgresql", "/var/lib/postgresql"]

CMD ["/usr/lib/postgresql/9.3/bin/postgres", "-D", "/var/lib/postgresql/9.3/main", "-c", "config_file=/etc/postgresql/9.3/main/postgresql.conf"]

Base image

Maintainer information

Install requirements

Set user to use when running the image

Application configuration

Export port on network

Export volumes

Start application

Docker compose

• Compose is a tool for defining and running multi-container Docker applications• /!\ 2 versions of docker-compose format

docker-compose.yml (version 1)postgres :image: postgres

cron:build: .dockerfile: Dockerfile-cronlinks:- postgres

web:build: .

volumes:- .:/code

ports:- "8000:8000"

links:- postgres

PostgreSQL database

CRON container

Load volume fromcurrent directory

Expose ports

Link containers

docker-compose.yml (version 2)

version: '2’

services:web:build: .ports:- ”8000:8000"volumes:- .:/code- logvolume01:/var/logdepends_on:- postgresql

postgres:image: postgres

volumes:logvolume01: {}

Version

Application

Postgresql

Volumes

Running containers with Docker composer

1. Define application containerCreate Dockerfile

2. Define container relationsCreate docker-compose.yml

3. Start containersdocker-compose up

4. Execute commandsdocker-compose run <container> <cmd>

Let’s try Docker…

Install Docker Toolbox

• Docker Toolbox’ll install all tools• https://www.docker.com/products/docker-toolbox

Virtualbox

Virtual machine

Docker Engine

Docker Machine

Docker CLI client

Docker Composer

Container

Create your first container

• Start Docker serverdocker-machine start default

• Load Docker connection parameterseval $(docker-machine env default)

• Create DockerfileFROM php

WORKDIR /var/www

ADD index.php .

EXPOSE 8080

ENTRYPOINT ["php", "-S", "0.0.0.0:8080"]

Start your first container

• Create index.phpecho '<?php echo ”Good morning!\n”; ?>' > index.php

• Build containerdocker build -t app1 .

• Check imagesdocker images | head

• Run the containerdocker run -t app1 -p 8080:8080 app1

• Connect to the websitecurl -v $(docker-machine ip):8080

Update the container

• Update application contentecho '<?php echo "Welcome!\n”; ?>' > index.php

• Connect to the websitecurl -v $(docker-machine ip):8080

• Still Good morning… What’s wrong?• Restart your container

Share your container

• Create an account on https://hub.docker.com• Tag your container

docker tag app1 <username>/app1• Connect on Dockerhub

docker login• Push container to Docker Hub

docker push <username>/app1• Connect on DockerHub website

https://hub.docker.com/<username>/app1/

cAdvisor

• Created by Google to monitor their own containers (lmctfy)• Analyzes resource usage and performance characteristics of running

containers.

Start cAdvisor• Run cAdvisor

docker run \--name=cadvisor \--restart always \--detach=true \--volume=/:/rootfs:ro \--volume=/var/run:/var/run:rw \--volume=/sys:/sys:ro \--volume=/var/lib/docker/:/var/lib/docker:ro \--publish=8001:8080 \google/cadvisor:latest

• Connect to the web interface

http://192.168.99.100:8001

Unit tests

Continuous integration/deployment

• Continuous integration• Run tests for each commit• Detect bugs

• Continuous deployment• Deploy application if tests success

GIT repository

CI CD

ProductionStaging

Developer

Gitlab

• Open source GIT repository management solution• Community and Enterprise editions

• GitHub alternative• https://about.gitlab.com

Start GitLab• Run GitLab

docker run --detach \--hostname gitlab.example.com\--publish 8000:80 \--name gitlab \--restart always \--volume /srv/gitlab/config:/etc/gitlab \--volume /srv/gitlab/logs:/var/log/gitlab \--volume /srv/gitlab/data:/var/opt/gitlab \gitlab/gitlab-ce:latest

• Connect to the web interface (Default password: root/5iveL!fe)

http://$(docker-machine ip):8000

Configure GitLab

• Connect on GitLab interface• Create a project• Create a user for Jenkins

Clone the repository

git clone http://192.168.99.100:8000/root/app1.gitcd app1/echo 'Welcome' > README.mdgit add README.mdgit commit README.md -m 'Add README.md'git push

Jenkins

• The most popular tool to build and deploy projects• Unittest• Continuous Integration• Continuous Delivery

• Plugins for everything!• Distribute work across multiple machines• https://jenkins.io

Start Jenkins

• Run Jenkins

docker run --detach \--publish 10000:8080 \--name jenkins \--restart always \jenkins:latest

• Connect to the web interface

http://$(docker-machine ip):10000

Configure Jenkins

• Install “Git plugin”• Restart Jenkins• Create a new project called “App1 - master”• Add GIT credentials• Poll SCM

* * * * *

• Executephpunit -c app

Lunch break!

EvaluationCreate a web hit counter with containers

Docker Engine

Redis

PHP application

Technical details

• 2 Docker containers:• Redis• Application (PHP application)

• Use PHP composer to install requirements• Use Docker Compose to start containers• Bonus:• 3 tiers architecture (Nginx/PHP/Redis)• SSL• Unit tests• …

Solution

Application files

<?php

require __DIR__ . '/vendor/autoload.php';Predis\Autoloader::register();

// Connect to redistry {

$redis = new Predis\Client('tcp://redis:6379');}catch (Exception $error) {

die($error->getMessage());}

// Get visitors$visitors = ($redis->exists('visitors')) ? $redis->get('visitors') : 0;

// Increment visitors$visitors++;$redis->set('visitors', $visitors);

// Display visitorsif ($visitors > 1) {

echo "<h1>There are $visitors visitors!</h1>\n";} else {

echo "<h1>There is $visitors visitor!</h1>\n";}

?>

{"require": {

"predis/predis": "^1.0.3"}

}

index.php composer.json

Docker files

FROM php:5-apache

# Install GITRUN apt-get update \

&& apt-get install -y git \&& apt-get clean \&& rm -rf /var/lib/apt/lists/*

# Install PHP composerRUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer

WORKDIR /var/www/html

# Add applicationADD . /var/www/html/

# Install application requirements with PHP composerRUN composer install

version: '2'services:application:

build: .ports:

- "80:80"depends_on:- redis

redis:image: redis:latest

Dockerfile docker-compose.yml

Q&A