Presentation from First Kontena meetup 2015/12/15. Examples: * Wordpress - https://github.com/kontena/examples/tree/master/wordpress * Wordpress Cluster - https://github.com/kontena/examples/tree/master/wordpress-cluster * MongoDB cluster - https://github.com/kontena/examples/tree/master/mongodb-cluster

1. Beginners Guide to Kontena
Lauri Nevala, Founder

2. Docker Basics
• Docker is an open source project to
• pack,
• ship
• run
any application as a lightweight container
© 2015 Kontena, Inc.

3. Pack
© 2015 Kontena, Inc.

4. Dockerfile
• Dockerfile is a text document that contains all the commands a
user could call on the command line to assemble an image
© 2015 Kontena, Inc.

5. Ship
© 2015 Kontena, Inc.

6. Docker Image
• docker build command builds an image from a Dockerfile and
a context.
• The build’s context is the files at a specified location PATH or
URL.
• Docker images can be stored in registry services
• Docker Hub
• Docker Registry
© 2015 Kontena, Inc.

7. Run
© 2015 Kontena, Inc.

8. Docker Run
• Running an application inside a container takes a single
command: docker run.
• $ docker run ubuntu:14.04 /bin/echo ‘Hello world’
• First we specified the docker binary and the command we wanted to
execute, run
• Next we specified an image: ubuntu:14.04. This is the source of the
container we ran.
• Next we told Docker what command to run inside our new container
© 2015 Kontena, Inc.

9. Example

10. Node.js Docker Application
• package.json
• index.js
• Dockerfile

11. Package.json
© 2015 Kontena, Inc.
{
"name": "docker_web_app",
"version": "1.0.0",
"description": "Node.js on Docker",
"author": “Lauri Nevala <lauri.nevala@kontena.io>",
"main": "index.js",
"dependencies": {
"express": "^4.13.3”
}
"scripts": {
"start": "node index.js"
}
}

12. Index.js
© 2015 Kontena, Inc.
'use strict';
const express = require('express');
// Constants
const PORT = 8080;
// App
const app = express();
app.get('/', function (req, res) {
res.send('Hello worldn');
});
app.listen(PORT);
console.log('Running on http://localhost:' + PORT);

13. Dockerfile
© 2015 Kontena, Inc.
FROM node:argon
# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
# Install app dependencies
COPY package.json /usr/src/app/
RUN npm install
# Bundle app source
COPY . /usr/src/app
EXPOSE 8080
CMD [ "npm", "start" ]

14. Building the Image
$ docker build -t <your username>/node-web-app .
• The -t flag lets you tag your image so it's easier to find later using the
docker images command
© 2015 Kontena, Inc.

15. Run the Image
$ docker run –d -p 49160:8080 –name node-web-app <your
username>/node-web-app
• Running the image with -d runs the container in detached mode,
leaving the container running in the background.
• The -p flag redirects a public port to a private port inside the container.
• The –name flag lets you name your image so it's easier to find it later.
• Image is first searched from local registry then from Docker Hub
© 2015 Kontena, Inc.

16. Test
$ curl http://<docker_host_ip>:49160
© 2015 Kontena, Inc.

17. Application Considerations
• Where to store images?
• Public hub
• Private registry
• How to setup?
• How to run applications on production environment?
• Deploying applications: how? who?
• Microservices and networking
• Multi-node environments: different availability zones, different cloud
providers
• High-Availability applications
• How to monitor applications?
• ???
© 2015 Kontena, Inc.

18. © 2015 Kontena, Inc.
“I don’t want to think all that,
I just want to develop my killer app!”

19. The Docker Platform

20. Deploying Application with Kontena
1. Setup Kontena
• http://www.kontena.io/docs/getting-started/quick-start
2. Create Kontena service
$ kontena service create -p 49160:8080 node-web-app nevalla/node-
web-app:latest
3. Deploy service
$ kontena service deploy node-web-app
© 2015 Kontena, Inc.

21. Familiar with Docker-compose?
© 2015 Kontena, Inc.
// kontena.yml
node-web-app:
image: registry.kontena.local/node-web-app:latest
ports:
- 80:8080
$ kontena app deploy

22. Monitoring Applications
• $ kontena app monitor
• $ kontena app logs
• $ kontena service stats
© 2015 Kontena, Inc.

23. Scaling Applications
© 2015 Kontena, Inc.
// kontena.yml
node-web-app:
image: registry.kontena.local/node-web-app:latest
instances: 2
ports:
- 80:8080
$ kontena app scale node-web-app 2

24. Stateful Services
• Services with persistent data (databases etc)
• Data won’t be lost between deploys
© 2015 Kontena, Inc.
// kontena.yml
redis:
image: redis:latest
stateful: true
// containers
redis-1
volumes_from: redis-1-volumes
redis-1-volumes

25. Linking Services
© 2015 Kontena, Inc.
// kontena.yml
wordpress:
image: wordpress:4.1
stateful: true
ports:
- 8080:80
links:
- mysql:wordpress-mysql
environment:
- WORDPRESS_DB_HOST=%{project}-mysql.kontena.local
env_file: wordpress.env
mysql:
image: mariadb:5.5
stateful: true
environment:
- MYSQL_ROOT_PASSWORD=secret

26. More complex example
MongoDB cluster
© 2015 Kontena, Inc.
mongo:
image: mongo:3.0
stateful: true
command: --replSet kontena --smallfiles
instances: 3
hooks:
post_start:
- cmd: sleep 10
name: sleep
instances: 1
oneshot: true
- cmd: mongo --eval "printjson(rs.initiate());"
name: rs_initiate
instances: 1
oneshot: true
- cmd: mongo --eval "printjson(rs.add('meetup-mongo-2'))"
name: rs_add2
instances: 1
oneshot: true
- cmd: mongo --eval "printjson(rs.add('meetup-mongo-3'))"
name: rs_add3
instances: 1
oneshot: true

27. © 2015 Kontena, Inc.

28. Thank You!
www.kontena.io