Setup Docker on Ubuntu at ProfitBricks

Table of Contents

• Introduction
• Operating System Support
• Virtual Datacenter Setup
• Installing Docker on Ubuntu
• Install nginx and Commit the Image

Introduction

This tutorial will walk you through the process of installing and validating that Docker is running correctly on your ProfitBricks servers. We will also illustrate how changes and commits work within a container by installing nginx.

Operating System Support

ProfitBricks supports multiple Linux distributions -- some that support Docker, some that do not. The following table outlines the OS images that currently support Docker.

• Ubuntu Trusty 14.04 (LTS)
• Ubuntu Precise 12.04 (LTS)
• CentOS 7

You can assign these images at the time you create a storage volume either through the DCD or via the API.

Virtual Datacenter Setup

Prior to continuing this tutorial it is recommended that you first try this within a test environment. The best way to set one up is by creating a separate virtual datacenter within your account that is fully segmented from your existing ProfitBricks production datacenter. You can do this via the API or Datacenter Designer (DCD).

First drag and drop a new assembly into the main pane. You will want to ensure it looks like the below diagram.

You will want to set the image for the storage volume to Ubuntu-14.04-LTS-server-2014-10-01. The default values for Cores and RAM should be fine for the purposes of this tutorial.

Once you're ready, provision the datacenter.

Installing Docker on Ubuntu

Docker requires the package apt-transport-https to be installed. This is included in the default Ubuntu-14.04 build at ProfitBricks.

Before you install Docker, you will need to add the Docker repository key to your keychain:

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

You should see a response similar to this:

Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --homedir /tmp/tmp.tNUh5zx96p --no-auto-check-trustdb --trust-model always --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9
gpg: requesting key A88D21E9 from hkp server keyserver.ubuntu.com
gpg: key A88D21E9: public key "Docker Release Tool (releasedocker) <docker@dotcloud.com>" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)

Next, update and install the lxc-docker package:

sudo sh -c "echo deb https://get.docker.com/ubuntu docker main > /etc/apt/sources.list.d/docker.list"
sudo apt-get update
sudo apt-get install lxc-docker

Finally, test that Docker is indeed working correctly by issuing the following command.

sudo docker run -i -t ubuntu /bin/bash

Change and Commit the Image

Once Docker is installed and you've shelled into your first container it is time to make a change to the configuration and commit it. We will go ahead and do a default install of nginx.

root@6e39ef6456de:/# apt-get update
root@6e39ef6456de:/# apt-get install nginx
root@6e39ef6456de:/# echo "daemon off;" >> /etc/nginx/nginx.conf
root@6e39ef6456de:/# chown -R www-data:www-data /var/lib/nginx

Now, type exit to drop out of the container.

Finally, commit the container:

docker commit 6e39ef6456de nginx-server

Be sure to swap out the container ID with your own.

Confirm your new container image exists:

root@docker001:~# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
nginx-server        latest              265400f6aeaa        11 seconds ago      231.3 MB

Go ahead and start up the container:

docker run -d -p 80:80 nginx-server /usr/sbin/nginx

You should see your new image by running:

sudo docker ps

This should show something similar to:

CONTAINER ID        IMAGE                 COMMAND             CREATED             STATUS              PORTS
5f6ad38bad2c        nginx-server:latest   "/usr/sbin/nginx"   3 seconds ago       Up 3 seconds        0.0.0.0:80->80/tcp

At this point you should be able to make a request using something like curl to validate that your nginx docker container is indeed serving the default page:

curl http://localhost

You should also be able to hit the same page from the public Internet using your publicly assigned ProfitBricks IP.