Introduction to Amazon EC2 Container Service (Amazon ECS) Hands On Lab

Transcription

1 Introduction to Amazon EC2 Container Service (Amazon ECS) Hands On Lab 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. This work may not be reproduced or redistributed, in whole or in part, without prior written permission from Amazon Web Services, Inc. Commercial copying, lending, or selling is prohibited.

2 Contents Introduction... 3 Overview... 3 Topics covered... 3 Prerequisites... 3 Amazon EC2 Container Service (Amazon ECS)... 3 Amazon EC2 Container Service... 3 Prerequisites components of Amazon ECS... 3 Scheduling Amazon ECS tasks... 4 Service definition parameters... 4 Service load balancing... 4 AWS Management Console... 4 Sign in to the AWS Management Console... 4 Create a KeyPair for use with the ECS hosts... 5 Create the lab environment using Cloud Formation... 5 Getting started with Amazon EC2 Container Service... 9 Register a Task Definition with the amazon-ecssample image... 9 Creating a service Deploy a New Application Version to the Service Update a running service End Your Lab Conclusion Additional Resources Amazon Web Services, Inc. and its affiliates. All rights reserved. 2

3 Introduction Overview This guide introduces you to the lab. The lab will give you the basic understanding of Amazon EC2 Container Service. It will demonstrate the basic steps required to get started with EC2 Container Service, creating an AWS Identity and Access Management (IAM) user, IAM group, Key Pair and a non-default Virtual Private Cloud (VPC). Topics covered By the end of this lab you will be able to: Create an Amazon ECS Task Definition. Populate an Amazon ECS Cluster. Deploy an application to an Amazon ECS Service. Prerequisites Some familiarity with IAM Roles and Amazon EC2 Instances is useful. Previous kowledge of Docker container technology or other Linux container technlogies is desirable. Amazon EC2 Container Service (Amazon ECS) Amazon EC2 Container Service Amazon EC2 Container Service (Amazon ECS) is a highly scalable, fast, container management service that makes it easy to run, stop, and manage Docker containers on a cluster of Amazon EC2 instances. Amazon ECS lets you launch and stop container-enabled applications with simple API calls, allows you to get the state of your cluster from a centralized service, and gives you access to many familiar Amazon EC2 features. You can use Amazon ECS to schedule the placement of containers across your cluster based on your resource needs, isolation policies, and availability requirements. Amazon ECS eliminates the need for you to operate your own cluster management and configuration management systems or worry about scaling your management infrastructure. Prerequisites components of Amazon ECS Amazon ECS contains the following components: Container Instance: An Amazon EC2 Instance that is running the Amazon ECS agent and has been registered into a cluster. Container: A Linux container that was created as part of a task. Cluster: A logical grouping of container instances that you can place tasks on. Task Definition, Task: A description of an application that contains one or more container definitions. A Task is a single instantiation of a Task Definition. Service: An Amazon ECS service allows you to run and maintain a specified number of instances of a task definition simultaneously Amazon Web Services, Inc. and its affiliates. All rights reserved. 3

4 Scheduling Amazon ECS tasks Amazon EC2 Container Service (Amazon ECS) is a shared state, optimistic concurrency system that provides flexible scheduling capabilities for your tasks and containers. The Amazon ECS schedulers leverage cluster state information provided by the Amazon ECS API to make an appropriate placement decision. Amazon ECS provides the service scheduler for long running stateless services and applications. The service scheduler ensures that the specified number of tasks are constantly running and reschedules tasks when a task fails (for example, if the underlying container instance fails for some reason). The service scheduler optionally also makes sure that tasks are registered against an Elastic Load Balancing load balancer. You can update your services that are maintained by the services scheduler, such as deploying a new task definition, or changing the running number of desired tasks. Service definition parameters A service definition defines which task definition to use with your service, how many instantiations of that task to run, and which load balancers (if any) to associate with your tasks. Service load balancing Your Amazon ECS service can optionally be configured to use Elastic Load Balancing to manage traffic. AWS Management Console Sign in to the AWS Management Console 1. Go to 2. Enter your address and password then click Sign in 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 4

5 Create a KeyPair for use with the ECS hosts This is covered in the Prerequisites document so it s not covered here, but, you will need the name of the key to create the Cloud Formation Stack. Create the lab environment using Cloud Formation There are some resources that need to be created for this lab that are outside the scope of this lab, but, need to be created in order to complete the lab. These items are: To execute the template do the following: 1. A new VPC for hosting the ECS hosts 2. Two Subnets (Both Public) 3. An Internet Gateway for the VPC 4. A role that ECS requires to run on resources in your account 5. An EC2 instance role for the ECS hosts 6. Security groups that allow http and https access to the ECS hosts 7. A load balancer for that directs http/s traffic for the ECS hosts 1. Go to the Cloud Formation Console by selecting it from the Services drop down: 2. Select Create Stack from the Dashboard: 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 5

6 3. Choose the third option Specify an Amazon S3 template URL and enter the following URL: 4. Click Next 4. Give it the stack name introlab and select the Key Pair that you created separately then click Next 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 6

7 5. Click Next Again 6. Check the checkbox to acknowledge that this template may incur costs (There is a cost for VPCs). You may have to scroll down the screen to see it at the bottom. Click Create once the checkbox is clicked Amazon Web Services, Inc. and its affiliates. All rights reserved. 7

8 7. Wait for the stack to complete execution (You can click the refresh icon to update screen ): 8. Once the stack is complete you can move on to the rest of the lab; 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 8

9 Getting started with Amazon EC2 Container Service Register a Task Definition with the amazon-ecssample image 9. In the AWS Console, select the EC2 Container Service from the Services menu. Click Get Started if necessary. If going through the Get Started Wizard, choose Custom task definition on the next page, then click the Next Step button. 10. If you are not yet at the Create custom Task Definition page, select Task Definitions on the left, and click Create New Task Definition. 11. Click the Select the Configure via JSON button. Task Definition: Describes the components of your application, such as the Docker containers to run, the resources they will use, and how they link together. For this lab, we will use a sample template provided to display a simple web page. You can modify the parameters in the Task Definition (for example, to provide more CPU resources or change the port mappings) to suit your particular applications. The Image parameter is the image to use for a container. This string is passed directly to the Docker daemon. Images in the Docker Hub registry are available by default. You can also specify other repositories with repository-url/image:tag. 12. The following task definition JSON file specifies two containers that are pulled from the Docker Hub repository. Cut and paste the below task definition into the JSON editor panel, overwriting the default contents. Then click the blue Save button. "family": "cornell-ecs-demo", "containerdefinitions": [ "volumesfrom": [ "portmappings": [ "hostport": 80, "containerport": 80 "command": null, "environment": [ "essential": true, "entrypoint": null, "links": [ "mountpoints": [ 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 9

10 "containerpath": "/usr/local/apache2/htdocs", "sourcevolume": "my-vol", "readonly": null "memory": 300, "name": "simple-app", "cpu": 10, "image": "httpd:2.4", "volumesfrom": [ "readonly": null, "sourcecontainer": "simple-app" "portmappings": [ "command": [ "/bin/sh -c \"while true; do echo '<html> <head> <title>amazon ECS Sample App</title> <style>body margin-top: 40px; background-color: #333; </style> </head><body> <div style=color:white;text-align:center> <h1>amazon ECS Sample App</h1> <h2>congratulations!</h2> <p>your application is now running on a container in Amazon ECS.</p>' > top; /bin/date > date ; echo '</div></body></html>' > bottom; cat top date bottom > /usr/local/apache2/htdocs/index.html ; sleep 1; done\"" "environment": [ "essential": false, "entrypoint": [ "sh", "-c" "links": [ "mountpoints": [ "memory": 200, "name": "busybox", "cpu": 10, "image": "busybox" "volumes": [ "host": "sourcepath": null, "name": "my-vol" ] 13. The task definition is now parsed; if you copied the JSON correctly, the console will show the new task definition registered in the cornell-ecs-demo family as defined in the JSON file. Click the Create button to register the task definition Amazon Web Services, Inc. and its affiliates. All rights reserved. 10

11 Creating a service When you create an Amazon ECS service, you specify several parameters that define what makes up your service and how it should behave. These parameters create a service definition. Use the following procedure to create a service. 14. Select Clusters in the left-hand navigation pane. 15. Select the default cluster by clicking on the cluster name default. 16. On the Services tab, click the Create button. 17. On the Create Service page, enter a unique name for your service in the Service name field. 18. In the Number of tasks field, enter 4 as the number of tasks you will launch and maintain on your cluster. 19. In the Elastic Load Balancing section, click on the NO ELB text in the Load Balancer:Host Port* dropdown menu, and select the Load Balancer starting with introlab from the drop-down list of ELBs. 20. Leave the Container Name: Host Port* drop-down list at the default. 21. In the Service Role section, click the drop-down box, and select the service role starting with introlab.this role has been prepared for the lab and it allows Amazon ECS to register and deregister container instances from the load balancer as tasks are placed on them. 22. Review your information, and choose Create Service. This will open the Service Details page for your new service. 23. Click the Tasks tab to make sure it is selected. Wait a few seconds and you will see the four tasks you requested getting created. You may need to click the refresh button for this to update. These tasks are running on the EC2 instances that were automatically provisioned into the ECS cluster by the CloudFormation template used to set up your lab environment. 24. Click the Events tab. This will show the progress of the various tasks associated with your service creation request. Click refresh until you get an event indicating that your service has reached a steady state. If you now click the Tasks tab you will see the tasks are all in the desired Running state. 25. Click on the Load Balancer s name to go to the Load Balancer dashboard Amazon Web Services, Inc. and its affiliates. All rights reserved. 11

12 26. With the load balancer selected via the check box, click the Instances tab. Wait until the four requested ECS Instances appear there and are listed as InService. This may take anywhere from 3-5 minutes. 27. Click the Description tab. 28. Copy the DNS name:. 29. Open a new browser tab, and type in then paste in the DNS name of the load balancer. Press enter to connect to the URL. 30. You should now see that the service is running if everything has been configured correctly you will see the sample app displayed as shown here: Deploy a New Application Version to the Service If you have updated the Docker image of your application, you can create a new task definition with that image and deploy it to your service, one task at a time. The service scheduler creates a task with the new task definition (provided there is an available container instance to place it on), and after it reaches the Running state, a task that is using the old task definition is drained and stopped. This process continues until all of the desired tasks in your service are using the new task definition. Update a running service 31. Return to the EC2 Container Service Dashboard, and select Task Definitions. 32. Select the check box for the task definition named cornell-ecs-demo, and click Create a New Revision. 33. For the purposes of this demo, update your task definition in the JSON editor with a change to the message displayed from Congratulations! to Thank you! In a production environment, you would probably change other aspects of your Task Definition. When finished editing, click the blue Create button. "family": "cornell-ecs-demo", "containerdefinitions": [ "volumesfrom": [ "portmappings": [ "hostport": 80, "containerport": Amazon Web Services, Inc. and its affiliates. All rights reserved. 12

13 "command": null, "environment": [ "essential": true, "entrypoint": null, "links": [ "mountpoints": [ "containerpath": "/usr/local/apache2/htdocs", "sourcevolume": "my-vol", "readonly": null "memory": 300, "name": "simple-app", "cpu": 10, "image": "httpd:2.4", "volumesfrom": [ "readonly": null, "sourcecontainer": "simple-app" "portmappings": [ "command": [ "/bin/sh -c \"while true; do echo '<html> <head> <title>amazon ECS Sample App</title> <style>body margin-top: 40px; background-color: #333; </style> </head><body> <div style=color:white;text-align:center> <h1>amazon ECS Sample App</h1> <h2>thank You!</h2> <p>your application is now running on a container in xamazon ECS.</p>' > top; /bin/date > date ; echo '</div></body></html>' > bottom; cat top date bottom > /usr/local/apache2/htdocs/index.html ; sleep 1; done\"" "environment": [ "essential": false, "entrypoint": [ "sh", "-c" "links": [ "mountpoints": [ "memory": 200, "name": "busybox", "cpu": 10, "image": "busybox" "volumes": [ "host": "sourcepath": null, "name": "my-vol" ] 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 13

14 34. In the navigation pane, select Clusters. 35. Click on the default cluster that your service resides in. 36. On the Services tab, check the box to the left of the service you want to update, and choose Update. 37. On the Update Service page, your service information is pre-populated. Change the task definition to the new cornell-ecs-demo:2, and click the blue Update Service button. This will deploy a new version of the application. Watch the Events tab to monitor the process of draining connections and stopping tasks, and finally check the Deployments tab after the service instances have reached a steady state. After the deployment is complete, return to your web browser and refresh the Load Balancer s URL (DNS name) to see the new version of the app. End Your Lab Follow these steps to close the console, end your lab, and evaluate the experience. 38. Return to the AWS Management Console Amazon Web Services, Inc. and its affiliates. All rights reserved. 14

15 39. Go to the EC2 Container Service Console. Select the Service and click Update : 40. Enter 0 for Number of tasks and click Update Service: 41. Now wait for the Running Count to equal Amazon Web Services, Inc. and its affiliates. All rights reserved. 15

16 42. Click on Delete on the top Right of the screen: 43. Click Delete on the popup: 45. Now go to the Cloud Formation Console and select the introlab stack: 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 16

17 46. Select Delete Stack Conclusion Congratulations! You now know how to: Create an Amazon ECS Task Definition. Populate an Amazon ECS Cluster. Deploy an application to an Amazon ECS Service. Additional Resources For more information about Amazon EC2 Container Service, go to For more information about Amazon EC2 Container Service pricing, go to Find more information about the AWS Certification program and other learning opportunities with AWS Training & Certification Amazon Web Services, Inc. and its affiliates. All rights reserved. 17

18 2015 Amazon Web Services, Inc. and its affiliates. All rights reserved. 18