/docker-ecs-lab

Build and Run a Containerized Web Application using Docker and Amazon Elastic Container Service (ECS)

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Build, Run and Deploy a Containerized Web Application using Docker and Amazon Elastic Container Service (ECS)

This lab is provided as part of AWS Summit Online, click here to explore the full list of hands-on labs.

ℹ️ You will run this lab in your own AWS account. Please follow directions at the end of the lab to remove resources to avoid future costs.

What will we build in this lab?

In this lab we will learn how to build and run a containerised application. We will then use the Amazon Elastic Container Service to host and run this container in the Cloud.

The diagram below illustrates the architecture the lab will be using.

Let's get started

SELECT REGION

  • On top right corner - Switch to N.Virginia (us-east-1)

First we will provision our network VPC and deploy an ECS Cluster The ECS cluster consists of the networking components and the underlying EC2 hosts that our containers will run in.

Provision the ECS Cluster - virtual network and hosts

Click the Launch Stack button below to provision your cluster.

This will take a few minutes while this is running you can move on with the next steps.

W3Schools

Provision the Dev Environment - Cloud9 IDE

While the cluster is provisioning let's initialize our development environment.

Click on the Launch Stack button below to provision your IDE in the cloud.

W3Schools
  • Once the Cloud9 Stack is completed, go to Services and go to Cloud9 on the AWS Web console
  • On the left hand pane click on Your Environments
  • Open the ECS Docker Cloud9 Env By clicking on Open IDE - this is your IDE in the cloud.
  • When you open cloud9 it will automatically clone this git repo onto it's local file system
  • This has all the files you need pre downloaded
  • Have a browse of the folder structure to see what files are in there

Install and run Docker in the Cloud9 IDE

Inside Cloud9

  • Open the Terminal change directory to the correct folder & Reset/Initiate the lab
$ cd ~/environment/ecs-docker-lab/

$ chmod +x Reset.sh

$ ./Reset.sh

$ clear

  • Install and run docker
$ sudo yum update -y

$ sudo yum install -y docker

$ sudo service docker start

$ sudo usermod -a -G docker ec2-user
  • Verify that docker is installed and running correctly
$ docker info

You have now installed docker successfully

Build and Run your Docker Container Locally

Let's build a docker image and run a docker container locally in cloud9

  • Open the index.html file inside the ecs-docker-lab folder inside DockerStaticSite-master folder and edit the Write something here

  • Save your edited HTML File

  • Build a container Image from the DockerFile

$ docker build -t staticsite:1.0 DockerStaticSite-master/
  • Run a Container from the freshly built image
$ docker run -itd \--name mycontainer \--publish 8080:80 staticsite:1.0
  • Test if your container is running locally
$ curl http://localhost:8080

If you get an HTML page as a response, then the container is running successfully - Well Done!

Setup a Docker Image Repository in AWS

Now that your containerized application is running locally, let's push your docker image to an Elastic Container Repository (ECR) in the cloud

Let's create an Elastic Container Repository. This will hold our container images.

  • Navigate to the ECS (Elastic Container Service) console on another tab and click on Repositories

Let's create an Elastic Container Repository. This will hold our container images.

  • Click on Create repository
  • Set the repository name as ecs-lab-repo
  • Your new repository will now be created

  • Click on ecs-lab-repo
  • Click on Permissions on the left to view permissions
  • Click on Edit policy JSON
  • In the text below replace YOUR_AWS_ACCOUNT_NUMBER with your actual AWS Account Number
  • Paste the edited text into the box and click Save
{
  "Version": "2008-10-17",
  "Statement": [
    {
      "Sid": "AllowPushPull",
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::YOUR_AWS_ACCOUNT_NUMBER:root"
      },
      "Action": [
        "ecr:BatchCheckLayerAvailability",
        "ecr:BatchGetImage",
        "ecr:CompleteLayerUpload",
        "ecr:GetDownloadUrlForLayer",
        "ecr:InitiateLayerUpload",
        "ecr:PutImage",
        "ecr:UploadLayerPart"
      ]
    }
  ]
}

Now we can push/pull images to/from this repo

Push you Docker Image into ECR

We will now push your new docker image to the cloud

  • Click on Images on the left

  • Click on "View Push Commands " (top right)

You will see a set of commands.

  • Go back to your cloud9 environment
  • Change directory into the correct folder
$ cd DockerStaticSite-master/

Follow the steps of the push commands to build and push the new modified image to the cloud repo

  • Copy paste the commands into cloud9 terminal

  • Make sure you run them in the right folder

  • You will see that the container image is pushed ========> to the cloud

  • Now your container has successfully been pushed to the cloud

    • Once pushed you will see an IMAGE URI for the new image, Copy This, we will need this later

Create an ECS Task Definition

A task definition is required to run Docker containers in Amazon ECS.

Your entire application stack does not need to exist on a single task definition, and in most cases it should not. Your application can span multiple task definitions by combining related containers into their own task definitions, each representing a single component.

In an earlier step we provisioned our networks and ECS cluster through clooudformation. That should have finishd by now. We will now deploy our newly pushed docker image to the cluster. So that we can run the container in the cloud.

  • Go to Services and navigate to the Elastic Container Service Dashboard.
  • In the navigation menu on the left, click Task Definitions.

  • Click Create new Task Definition
  • Select Launch Type as EC2 and click next

  • Put in the Task Definition Name as simplewebtask
  • Scroll down and click Add Container

  • Put in the name as WebContainer
  • In Image paste your IMAGE URI that we copied earlier
  • In Memory Limit put in 128
  • In Port Mapping Host Port 80 | Container Port 80
  • Scroll to bottom and click Add to add in the container
  • Scroll to bottom and click Create to complete creating the task

This will create a new Task. Note the Version Number. The new version will use the latest container image. i.e. the image that you just pushed.

Create an ECS Service

An Amazon ECS service enables you to run and maintain a specified number of instances of a task definition simultaneously in an Amazon ECS cluster.

  • in the left navigation pane, click Clusters.

  • in the Clusters window, click default

  • on the Services tab,
  • Click Create

Enter the folowing parameters

  • Launch Type is EC2
  • Task Definition simplewebtask
  • Cluster default
  • Service Name webservice
  • Number of Tasks 1

Next Step : Configure Network

  • Health check grace period 10 Seconds
  • Load balancer type is classic load balancer
  • Disable Service Discovery if it's present

Next Step : Setup Auto Scaling

  • Select Do NOT adjust the services desired count

Next Step

  • click Create Service

  • Once create is complete click View Service

Well done your ECS Service has now been created

Now ECS is provisioning the desired number of Tasks in our cluster. Once created the tasks will register with our loadbalancers which we provisioned in our initial cloudformation script.

Viewing the Running Website

In your ecs service page

  • Click on the details tab
  • Click on myloadbalancer , this will take you to you load balancer page
  • Copy your load balancers DNS Name and paste in a new browser tab

Congratulations! Your Containerized web application is now running in the cloud

Troubleshooting steps
## If your Service Creation Failed try the steps below to redeploy

- click **Update** then click on **Revision**

- **Revision:** select the *latest version that you just created*

- **Force New Deployment --** check this box & turn it on

- click **Next Step**

- on **Step 2**, click **Next Step**

- on **Step 3**, click **Next Step**

- on **Step 4**, click **Update Service**

This will deploy a new version of the application.

* on the **Launch Status** page, click **View Service**

* on the **Service: myService** page, click the **Events** tab.

## Check if the new version on the application has successfully deployed

Wait a few minutes. Monitor the process of draining connections and
stopping tasks till the service reaches a steady state.

You may need to click the **Refresh** button to see the new events.

Once the events says "service webService has reached a steady state."
  • Go to EC2 service page

  • On the left hand pane click on load balancers

  • search and click on myLoadBalancer

  • Paste in the Load Balancer's DNS name to see the new version of the app running in the cloud

Congratulations! Your Containerized web application is Now Running in the cloud

Clean Up Steps

It is important to execute these steps in order to no longer incur additional charges for the resources that you have provisioned.

  • DELETE the Cloud formation stack for the ecs cluster

  • DELETE the cloud for the cloud9 dev environment

  • DELETE any child cloudformation stacks spawned during this lab

Further reading

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/docker-basics.html

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/Welcome.html

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/AWS_Fargate.html