Cheap Minecraft Server in AWS with Docker and Traefik

minecraft-like figure on the grass

According to the Minecraft Realms plan pricing page, you can get a realms server at around £5.59 per month. You get some nice conveniences there but… I refuse to pay much at all when I can throw some infrastructure together myself in the cloud to create the ultimate cheap Minecraft server.

Considering my Docker instance running Traefik hosts another 3 or 4 of my personal services along with a Minecraft server, then this solution only costs me around £1.50 a month.

I chose to go with a single AWS EC2 instance that runs Docker. Minecraft runs in a container and sits alongside other personal websites and services that I host there too.

I use Traefik to route traffic coming in to this single host for various TCP ports as well as HTTP(s) on different hostnames. This essentially levels up the cost savings even further as I don’t need multiple EC2 instances (one for each service), and I don’t even need to pay for something like an application or network load balancer, as Traefik does this for me.

A Quick Review of Alternatives

There are other alternatives to consider if you’re looking for a cheap Minecraft server, so don’t take this as being the only option. Here is what I’ve used in the past before settling on my current solution:

  • Minecraft on a dedicated cloud VM. If you just want a dedicated Minecraft VM in the cloud, then DigitalOcean is a good, cheap option. You can also get fairly cheap instances Vultr.
  • Running Minecraft on my own personal Raspberry Pi Kubernetes Cluster. I was even able to expose it over the internet for friends to play on by leveraging a Pi device as a dedicated router. I then used port forwarding to get it working through my double NAT setup. The ARM container was a little slow as a server for more than 2 or 3 players on Raspberry Pi hardware though.
  • Minecraft Server on a home PC / Workstation, with port forwarding to allow other players to connect. This is not ideal, especially on Windows machines or systems that you don’t want to leave running 24/7 as you would for a dedicated server.
  • Various other Minecraft-as-a-service providers. These are decent options in some cases. However for me price and control are important, and I much prefer to self host in this case.

Cheap Minecraft Server in AWS EC2 with Traefik

I used my Cheap Traefik EC2 Docker Hosting solution as the base. You can read that article to get access to the CDK resources required to deploy it yourself.

The cost benefits to using this particular recipe are:

  • EC2 Graviton2 ARM based processor – slightly cheaper to run than Intel and AMD. The downside is more limited software choices. You need to make sure you use ARM compatible packages or Docker images.
  • Spot instance – this has massive savings over a normal lifecycle EC2 instance. The downside is that it can be terminated at any time with only a couple of minutes of notice. When using these you need to make sure you have good data persistence that is not local to the EC2 instance. I personally use a mounted EFS volume. It is re-attached to a new instance from the autoscaling group if the old instance is terminated.

If you don’t use the CDK solution I mentioned above, then alternatively deploy yourself an EC2 instance. Give it an elastic IP address, set up the Security Group ingress rules accordingly, and get shell access. First thing you’ll want to install is Docker, then you’re pretty much good to go.

Minecraft Docker Image

I found a great Minecraft Docker image that is well maintained and has the correct ARM image builds for use on Graviton2 hardware. Check out itzg/minecraft-server. There are other arch builds there that’ll run on just about any other platform.

Docker Compose Service

If you use docker-compose, then here is the simple service definition to get things running.

version: "3"

    external: true
    external: false

    image: itzg/minecraft-server:2021.1.0-multiarch-latest
      EULA: "TRUE"
      VERSION: "1.16.5"
      MAX_TICK_TIME: "-1"
      TYPE: "BUKKIT"
      - traefik.port=25565
      - web
      - /data/mc:/data

The docker-compose definition will run a Docker container using the latest multiarch image (which will run on ARM devices). When starting, the container will prepare and run a Minecraft 1.16.5 server. It will also use Bukkit and enable auto pause. The game server does not tick over when there are no players connected.

Traefik Configuration

In the docker-compose definition above, you might have noticed the container labels. The labels prefixed with traefik are used to inform Traefik of how to route network traffic.

the cheap minecraft server uses a Traefik TCP router with HostSNI *
The TCP router using HostSNI on *

In our case, TCP connections are required on port 25565 and HostSNI is used to route those coming in for * (all hosts). The TCP connections on port 25565 go to Traefik, and based on this rule, directed to the Minecraft container.

There is one limitation to be aware of here, and that is that you can only use HostSNI with * for connections that do not use TLS. This is because Server Name Indication (SNI) is an extension of the TLS protocol.

I don’t believe Minecraft supports TLS in any case though. It just means that you won’t be able to have more than one Minecraft server container using the same port running on the single Docker host.

Finishing Off Configuration

Lastly, you might want to point a convenient Host record (A record) to your AWS EC2 Elastic IP address. For example: ->

All being well, you should now be able to find and connect to your server.

minecraft server listing

Minimal Cost Web Hosting With Spot, Graviton2, EFS, Traefik, & Let’s Encrypt


I’m constantly searching for minimal cost web hosting solutions. To clarify that statement, I mean ‘dynamic‘ websites, not static. At the moment I am running this blog and a bunch of others on a Raspberry Pi Kubernetes cluster at home. I got to thinking though, what happens if I need to move? I’ll have an inevitable period of downtime. Clearly self-hosting from home has it’s drawbacks.

I’ve run my personal dynamic websites from AWS before (EC2 with a single Docker instance), but used an application load balancer (ALB) to help with routing traffic to different hostnames. The load balancer itself adds a large chunk of cost, and storage was EBS, a little more difficult to manage when automating host provisioning.

A Minimal Cost Web Hosting Infrastructure in AWS

I wanted to find something that minimises costs in AWS. My goal was to go as cheap as possible. I’ve arrived at the following solution, which saves on costs for networking, compute, and storage.

minimal cost web hosting Infrastructure diagram
  • AWS spot EC2 single instance running on AWS Graviton2 (ARM).
  • EFS storage for persistence (a requirement is that containers have persistence, as I use wordpress and require MySQL etc…)
  • Elastic IP address
  • Simple Lambda Function that manages auto-attachment of a static, Elastic IP (EIP) to the single EC2 instance. (In case the spot instance is terminated due to demand/price changes for example).
  • Traefik v2 for reverse proxying of traffic hitting the single EC2 instance to containers. This allows for multiple websites / hosts on a single machine

It isn’t going to win any high availability awards, but I’m OK with that for my own self-hosted applications and sites.

One important requirement with this solution is the ability to run dynamic sites. I know I could be doing this all a lot easier with S3/CloudFront if I were to only be hosting static sites.

Using this setup also allows me to easily move workloads between my home Kubernetes cluster and the cloud. This is because the docker images and tags I am using are now compatible between ARM (on Raspberry Pi) and ARM on Graviton2 AWS docker instances.

The choices I have gone with allow me to avoid ‘cloud lock in’, as I can easily switch between the two setups if needed.

Cost Breakdown

I’ve worked out the monthly costs to be roughly as follows:

  • EC2 Graviton2 ARM based instance (t4g.medium), $7.92
  • 3GB EFS Standard Storage, $0.99
  • Lambda – will only invoke when an EC2 instance change occurs, so cost not even worth calculating
  • EIP – free, as it will remain attached to the EC2 instance at all times
minimal cost web hosting solution - spot instance pricing chart
Current Spot Instance pricing for t4g.medium instances

If you don’t need 4GB of RAM, you can drop down to a t4g.small instance type for half the cost.

Total monthly running costs should be around $8.91.

Keep in mind that this solution will provide multiple hostname support (multiple domains/sites hosted on the same system), storage persistence, and a pretty quick and responsive ARM based Graviton2 processor.

You will need to use ARM compatible Docker images, but there are plenty out there for all the standard software like MySQL, WordPress, Adminer, etc…

How it Works

The infrastructure diagram above pretty much explains how everything fits together. But at a high level:

  • An Autoscaling Group is created, in mixed mode, but only allows a single, spot instance. This EC2 instance uses a standard Amazon Linux 2 ARM based AMI (machine image).
  • When the new instance is created, a Lambda function (subscribed to EC2 lifecycle events) is invoked, locates a designated Elastic IP (EIP), and associates it with the new spot EC2 instance.
  • The EC2 machine mounts the EFS storage on startup, and bootstraps itself with software requirements, a base Traefik configuration, as well as your custom ‘dynamic’ Traefik configuration that you specify. It then launches the Traefik container.
  • You point your various A records in DNS to the public IP address of the EIP.
  • Now it doesn’t matter if your EC2 spot instance is terminated, you’ll always have the same IP address, and the same EFS storage mounted when the new one starts up.
  • There is the question of ‘what if the spot market goes haywire?’ By default the spot price will be allowed to go all the way up to the on-demand price. This means you could potentially pay more for the EC2 instance, but it is not likely. If it did happen, you could change the instance configuration or choose another instance type.

Deploying the Solution

As this is an AWS opinionated infrastructure choice, I’ve packaged everything into an AWS Cloud Development Kit (AWS CDK) app. AWS CDK is an open source software development framework that allows you to do infrastructure-as-code. I’ve used Typescript as my language of choice.

Clone the source from GitHub

Deploy Requirements

You’ll need the following requirements on your local machine to deploy this for yourself:

  • NodeJS installed, along with npm.
  • AWS CDK installed globally (npm install -g aws-cdk)
  • Define your own traefik_dynamic.toml configuration, and host it somewhere where the EC2 instance will be able to grab it with curl. Note, that the Traefik dashboard basic auth password is defined using htpasswd.
htpasswd -nb YourUsername YourSuperSecurePasswordGoesHere
  • An existing VPC in your account to use. The CDK app does not create a VPC (additional cost). You can definitely use your default account VPC that is already available in all accounts though.
  • An existing AWS Keypair
  • An existing Elastic IP address (EIP) created, and tagged with the key/value of Usage:Traefik (this is for the Lambda function to identify the right EIP to associate to the EC2 instance when it starts)
Tag requirement for the Elastic IP Address

I haven’t set up the CDK app to pass in parameters, so you’ll just need to modify a bunch of variables at the top of aws-docker-web-with-traefik-stack.ts to substitute your specific values for the aforementioned items. For example:

const vpcId = "your-vpc-id";
const instanceType = "t4g.medium"; // t4g.small for even more cost saving
const keypairName = "your-existing-keypair-name";
const managementLocationCidr = ""; // your home / management network address that SSH access will be allowed from. Change this!
const traefikDynContentUrl = ""; // this should point to your own dynamic traefik config in toml format.
const emailForLetsEncryptAcmeResolver = 'email = ""'; // update this to your own email address for lets encrypt certs
const efsAutomaticBackups = false; // set to true to enable automatic backups for EFS

Build and Deploy

Build the Typescript project using npm run build. This compiles the CDK and the EIP Manager Lambda function typescript.

At this point you’re ready to deploy with CDK.

If you have not used CDK before, all you really need to know is that it takes the infrastructure described by the code (typescript in this case), and coverts it to CloudFormation language. The cdk deploy command deploys the stack (which is the collection of AWS resources defined in code).


# Check what changes will be made first
cdk diff

# Deploy
cdk deploy

Testing a Sample Application Stack

Here is a sample docker-compose stack that will install MySQL, Adminer, and a simple WordPress setup.

SSH onto the EC2 instance that is provisioned, and use docker-compose up -d deploy the compose example stack. Just remember to edit and change the template passwords in the two environment variables.

You’ll also need to update the hostnames to your own (from, and point those A records to your Elastic public IP address.

One more thing, there is a trick to running docker-compose on ARM systems. I personally prefer to grab a docker image that contains a pre-built docker-compose binary, and shell script that ties it together with the docker-compose command. Here are the steps if you need them (run on the EC2 instance that you SSH onto):

sudo curl -L --fail -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose

For your own peace of mind, make sure you inspect that githubusercontent script yourself before downloading, as well as the docker image(s) it references and pulls down to run docker-compose.

Tear Down

To destroy the stack, simply issue the cdk destroy command. The EFS storage is marked by default with a retain policy, so it will not be deleted automatically.

cdk destroy AwsDockerWebWithTraefikStack
deleting the minimal cost web hosting solution cdk stack


If you’re on the look out for a minimal cost web hosting solution, then give this a try.

The stack uses the new Graviton2 based t4g instance type (ARM) to help achieve a minimal cost web hosting setup. Remember to find compatible ARM docker images for your applications before you go all in with something like this.

The t4g instance family is also a ‘burstable’ type. This means you’ll get great performance as long as you don’t use up your burst credits. Performance will slow right down if that happens. Keep an eye on your burst credit balance with CloudWatch. For 99% of use cases you’ll likely be just fine though.

Also remember that you don’t need to stick to AWS. You could bolt together services from any other cloud provider to do something similiar, most likely at a similar cost too.

Quick and Easy Local NPM Registry With Verdaccio and Docker

container storage

Sometimes it can be useful to be able to npm publish libraries or projects you’re working on to a local npm registry for use in other development projects.

This post is a quick how-to showing how you can get up and running with a private, local npm registry using Verdaccio and docker compose.

Verdaccio claims it is a zero config required NPM registry, and that is pretty much correct. You can have it up and running in under 5 minutes. Here’s how:

Local NPM Registry Quick Start

Clone verdaccio docker-examples and then change directory into the docker-examples/docker-local-storage-volume directory.

git clone
cd docker-examples/docker-local-storage-volume

This particular sample docker-compose configuration gives you a locally run verdaccio instance along with persistence via local volume mount.

From here you can be up and running by simply issuing the following docker-compose command:

docker-compose up -d

However if you do want to make a few tweaks to the configuration, simply load up the conf/config.yaml file in your editor.

I wanted to change the max_body_size to a higher value to allow for larger npm packages to be published locally, so I added:

max_body_size: 500mb

If you haven’t yet started the local docker container, start it up with docker-compose up.


Now all you need to do is configure your local npm settings to use verdaccio on http://localhost:4873. This is default host and port that verdaccio is configured to listen on when running in docker locally).

Then add an npm user for local development:

npm adduser --registry http://localhost:4873

To use your new registry at a project level, you can create a .npmrc file in your local projects with the following content:


Of course replace the scope of @shogan with the package scope of your choosing.

To publish a module / package locally:

npm publish --registry http://localhost:4873

Other Examples

There are lots more verdaccio samples and configurations that you can use in the docker-examples repository. Take a look to find these, including Kubernetes resources to deploy if you prefer running there for a local development setup.

Also refer to the verdaccio configuration page for more examples and documentation on the possible config options.

AWS CodeBuild local with Docker

AWS have a handy post up that shows you how to get CodeBuild local by running it with Docker here.

Having a local CodeBuild environment available can be extremely useful. You can very quickly test your buildspec.yml files and build pipelines without having to go as far as push changes up to a remote repository or incurring AWS charges by running pipelines in the cloud.

I found a few extra useful bits and pieces whilst running a local CodeBuild setup myself and thought I would document them here, along with a summarised list of steps to get CodeBuild running locally yourself.

Get CodeBuild running locally

Start by cloning the CodeBuild Docker git repository.

git clone

Now, locate the Dockerfile for the CodeBuild image you are interested in using. I wanted to use the ubuntu standard 3.0 image. i.e. ubuntu/standard/3.0/Dockerfile.

Edit the Dockerfile to remove the ENTRYPOINT directive at the end.

# Remove this -> ENTRYPOINT [""]

Now run a docker build in the relevant directory.

docker build -t aws/codebuild/standard:3.0 .

The image will take a while to build and once done will of course be available to run locally.

Now grab a copy of this script and make it executable.

curl -O
chmod +x ./

Place the shell script in your local project directory (alongside your buildspec.yml file).

Now it’s as easy as running this shell script with a few parameters to get your build going locally. Just use the -i option to specify the local docker CodeBuild image you want to run.

./ -c -i aws/codebuild/standard:3.0 -a output

The following two options are the ones I found most useful:

  • -c – passes in AWS configuration and credentials from the local host. Super useful if your buildspec.yml needs access to your AWS resources (most likely it will).
  • -b – use a buildspec.yml file elsewhere. By default the script will look for buildspec.yml in the current directory. Override with this option.
  • -e – specify a file to use as environment variable mappings to pass in.

Testing it out

Here is a really simple buildspec.yml if you want to test this out quickly and don’t have your own handy. Save the below YAML as simple-buildspec.yml.

version: 0.2

      java: openjdk11
      - echo This is a test.
      - echo This is the pre_build step
      - echo This is the build step
      - bash -c "if [ /"$CODEBUILD_BUILD_SUCCEEDING/" == /"0/" ]; then exit 1; fi"
      - echo This is the post_build step
    - '**/*'
  base-directory: './'

Now just run:

./ -b simple-buildspec.yml -c -i aws/codebuild/standard:3.0 -a output /tmp

You should see the script start up the docker container from your local image and ‘CodeBuild’ will start executing your buildspec steps. If all goes well you’ll get an exit code of 0 at the end.

aws codebuild test run output from a local Docker container.

Good job!

This post contributes to my effort towards 100DaysToOffload.

Streamlining your Kubernetes development process with Draft (and Helm)

Draft is a tool built for developers who do their dev work against a Kubernetes environment (whether it be a live cluster of a Minikube instance).

It really helps speed up development time by helping out with the code -> build -> run -> test dev cycle. It does this by scaffolding out a Dockerfile and Helm Chart template pack customised for your app with a single command and then by building and deploying your application image to your Kubernetes environment with a second.

Setting up Draft and a basic .NET Core Web API project

First off, make sure you have already set up your kubectl configuration to be able to talk to your Kubernetes cluster, and have also setup and configured Helm.

Set the Draft binary up in a known system path on your machine after downloading it from the Draft Releases page.

Run draft init to initialise Draft. It’ll drop it’s configuration in a subdirectory of your user profile directory called .draft.

Create a new .NET Core 2.1 project and select Web API as the type.

Open a shell and navigate over to the root project directory of your new .NET Core 2.1 app. E.g. cd solution\projectname

Run draft create to setup Draft with your new project. This is where the Draft magic happens. Essentially, Draft will:

  • Detect your application code language. (In this case csharp)
  • Create a Dockerfile for your app
  • Set up a Helm chart and necessary template structure to easily deploy your app into Kubernetes direct from your development machine

You should see output similar to this:

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> draft create
--> Draft detected JSON (97.746232%)
--> Could not find a pack for JSON. Trying to find the next likely language match...
--> Draft detected XML (1.288026%)
--> Could not find a pack for XML. Trying to find the next likely language match...
--> Draft detected csharp (0.914658%)
--> Ready to sail

At this point you could run draft up and if you have a container registry setup for Draft on your machine already, it would build and push your Docker image and then deploy your app into Kubernetes. However, if you don’t yet have a container registry setup for Draft you’ll need to do that first.

draft config set registry

PS, just make sure your local development machine has credentials setup for your container registry. E.g. Docker Hub.

Run your app with Draft (and help from Helm)

Now run draft up

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> draft up
Draft Up Started: 'draftdotnetcorewebapi': 01CH1KFSSJWDJJGYBEB3AZAB01
draftdotnetcorewebapi: Building Docker Image: SUCCESS ⚓  (45.0376s)
draftdotnetcorewebapi: Pushing Docker Image: SUCCESS ⚓  (10.0875s)
draftdotnetcorewebapi: Releasing Application: SUCCESS ⚓  (3.3175s)
Inspect the logs with `draft logs 01CH1KFSSJWDJJGYBEB3AZAB01`

Awesome. Draft built your application into a Docker image, pushed that image up to your container registry and then released your application using the Helm Chart it scaffolded for you when you initially ran draft create.

Take a look at Kubernetes. Your application is running.

kubectl get deployments

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> kubectl get deployments
NAME                           DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
draftdotnetcorewebapi-csharp   1         1         1            1           7m

Iterating on your application

So your app is up and running in Kubernetes, now what?

Let’s make some changes to the Helm chart to get it deploying using a LoadBalancer (or NodePort if you’re using Minikube). Let’s also add a new Api Controller called NamesController that simply returns a JSON array of static names with a GET request.

using Microsoft.AspNetCore.Mvc;

namespace draftdotnetcorewebapi.Controllers
    public class NamesController : ControllerBase
        public ActionResult<IEnumerable> Get()
            return new string[] { "Wesley", "Jean-Luc", "Damar", "Guinan" };

Change your charts/csharp/values.yaml file to look like this (use NodePort if you’re trying this out with Minikube):

using Microsoft.AspNetCore.Mvc;
# Default values for c#.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.
replicaCount: 1
  pullPolicy: IfNotPresent
  name: dotnetcore
  type: LoadBalancer
  externalPort: 8080
  internalPort: 80
    cpu: 1
    memory: 256Mi
    cpu: 250m
    memory: 256Mi
  enabled: false

Run draft up again. Your app will get built and released again. This time you’ll have a LoadBalancer service exposed and your updated application with the new API endpoint will be available within seconds.

This time however Draft was clever enough to know that it didn’t need a new Helm release. Using Helm, it determined that an existing release was already in place and instead did a helm upgrade underneath the covers. Test it for yourself with a helm list

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> helm list
NAME                            REVISION        UPDATED                         STATUS          CHART                           NAMESPACE
draftdotnetcorewebapi           2               Wed Jun 27 23:10:11 2018        DEPLOYED        csharp-v0.1.0                   default

Check the service’s External IP / URL and try it out by tacking on /api/names on the end to try out the new Names API endpoint.

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi>PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> kubectl get service draftdotnetcorewebapi-csharp -o wide
NAME                           TYPE           CLUSTER-IP     EXTERNAL-IP                                                               PORT(S)          AGE       SELECTOR
draftdotnetcorewebapi-csharp   LoadBalancer   8080:31381/TCP   32m       app=draftdotnetcorewebapi-csharp

Draft clean up

To take your app down and delete the Helm release, simply issue a draft delete on the command line.

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> helm list
NAME                            REVISION        UPDATED                         STATUS          CHART                           NAMESPACE
draftdotnetcorewebapi           2               Wed Jun 27 23:10:11 2018        DEPLOYED        csharp-v0.1.0                   default

Check the service’s External IP / URL and try it out by tacking on /api/names on the end to try out the new Names API endpoint.

PS C:\git\draftdotnetcorewebapi\draftdotnetcorewebapi> draft delete
app 'draftdotnetcorewebapi' deleted

That’s all there is to it.

Draft really helps ease the monotony and pain of setting up a new project and getting it all working with Docker and Kuberenetes. It vastly improves your development cycle times too. Check it out and start using it to save time!

Deploying a simple linked container web app with Docker

This is a simple guide on how to deploy a multi-container ‘linked’ web app using Docker.

If you have not yet installed or set up a Docker host to run the containers on, here is my guide on setting up a basic uBuntu 16.04 Docker host VM.

The ‘web app’ we’ll be looking at how to deploy will consist of two basic components – a MySQL database for the back-end, and a simple PHP script for the ‘web front-end’ which simply connects to the MySQL container and displays some info from a database table.


For the MySQL container we’ll be using the official Docker repo ‘mysql-server’ image, and for our web front-end, we’ll be creating our own Docker image using a custom Dockerfile we’ll craft ourselves, based on an uBuntu 15.04 image.

This means we’ll be covering the following Docker basics:

  • Running docker containers
  • Linking docker containers (more secure than exposing ports directly)
  • Creating custom docker images using a Dockerfile
  • Building a custom image

Start off by creating a new directory in your home directory called ‘web01’ to create and store the Dockerfile we’ll using to build our custom web front-end image. Then create an emtpy file called ‘Dockerfile’ in this directory and edit it using your favourite text editor. I’m using nano for this.



This is what your new Dockerfile should look like:


The commands do the following:

  • FROM – tells docker build to base this image build on the ubuntu:15.04 image
  • RUN – strings a few apt-get commands together to install apache, php5, and a few other tools like curl. This is important, as every RUN command in a Dockerfile creates a new image layer, and we don’t want our image to contain too many layers.
  • The last RUN command grabs the content from a gist I created which is a basic PHP script, and places it in the /var/www/html directory in the container, then deletes the default index.html file that apache places there. This is the script that will connect to our MySQL container and display some basic info (our basic ‘web app’).
  • EXPOSE – exposes port 80 so we can map this to our Docker host and access the website outside of the container.
  • CMD – runs the apache2 service with PID 1 when the container starts.

Now you can build the Dockerfile and create your own custom image, which is what will be used to start the web container later.

Use the following build command to build the new image from your custom Dockerfile

docker build -t=”web01image” ~/web01/Dockerfile

Run ‘docker images’ after the build completes and you should see the new image listed:


Next, you’ll run a new container using the official mysql-server image from the Docker repository. You won’t yet have this image locally, but the command will automatically download the image for you.

docker run –name db01 -e MYSQL_ROOT_PASSWORD=MyRootPassword -d mysql/mysql-server:latest

Note that I’ve called my container ‘db01’ and given it a root password of ‘MyRootPassword’. The -e parameter specifies that an environment variable called MYSQL_ROOT_PASSWORD inside the container should be given the value of ‘MyRootPassword’. The MySQL container then uses this environment variable to setup the root user for MySQL when the container starts.

Now that the database container is up and running (verify by running ‘docker ps’ to check its running), you can deploy the custom web container using your image you created above. In this docker run command, you’ll also link  the web container to the db01 container you previously started up using the –link parameter. This is important to link the two containers.

The web container will be given environment variables with information telling it about the networking config of the DB container. These environment variables will then be access by the simple web PHP script to tell it where to find the database server, and what credentials to use to connect.

docker run –name=web01 –link=db01:mysql -d -p=80:80 web01image

Important: notice that in the –link parameter, the name of the database/MySQL container is specified. Make sure you use the exact name you gave your MySQL database container here – this ensures that the linking of the two containers is correct. The last ‘web01image’ bit specifies to base the container you are running off of the newly built ‘web01image’.

The -p parameter maps the exposed port 80 in the container to port 80 on the docker host, so you’ll be able to access the website by using http://dockerhost:80

Check that the new web container and previously created MySQL container are running by using the ‘docker ps’ command.


Out of interest, this is what the PHP script looks like (this is what is downloaded and placed on the web container as a RUN build step in the Dockerfile you created above):

You can see the environment variables that the PHP script grabs (top of the script) to establish the database connection from the docker container. These environment variables are what are created and populated by linking the web container to the db container using the –link parameter.

Lastly, you may want to create a sample database, table and some data for the simple ‘web app’ to display after it connects to the database container. Issue the following ‘docker exec’ command, which will add the sample database, create a sample table, and add some sample data.

Make sure you change the ‘MyRootPassword’ bit to whatever root MySQL password you chose when you ran the MySQL container above, and ensure you run exec against the name of the MySQL container you chose (I used db01). Keep the database name and the rest of the command intact, as the PHP script relies on these staying the same.

docker exec db01 mysql -u root -pMyRootPassword -e “create database testdb1; use testdb1; CREATE TABLE events (id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, name VARCHAR(20), signup_date DATE); INSERT INTO events (id,name,signup_date) VALUES (NULL, ‘MySpecialEvent’, ‘2016-06-11’);”

Finally, browse to http://dockerhostnameorip and you should see the simple PHP script display some basic info, stating it was able to connect to the MySQL server and display the sample data in the database.