Detailed Instructions

5.1 Create a new task definition for the MXNet container

In this step, you will create a new task definition for a deep learning container running the MXNet framework, with a placement constraint to ensure tasks run only on certain instance types.

  1. Sign-in to the AWS management console and open the Amazon ECS console at https://console.aws.amazon.com/ecs/.

  2. Select Task Definitions from the left-hand menu.

  3. Click Create new Task Definition.

  4. Click EC2 and then Next step.

  5. In Task Definition Name, enter mxnet.

  6. Click Add Container.

  7. In the Add container dialog, under Standard:

    1. In Container name, enter mxnet

    2. In Image, paste the repository URI and add the latest tag.

      205094881157.dkr.ecr.us-west-2.amazonaws.com/mxnet:latest

    3. In Memory Limits (MiB), set Hard Limit to 2048.

    4. Click Add.

  8. In Constraint, click Add constraint.

  9. Set the Expression to use an instance type that is currently running in the cluster. For example if one of the instance types was an c4.large, you would enter:

    attribute:ecs.instance-type == c4.large

    To check the instance types running, open the Clusters view in a new tab, click catsndogsECScluster and select the ECS Instances tab.

    From the pop-up window, click the cog button, , and select ecs.instance-type.

    Scroll along the list of instances to see the ecs.instance-type value.

  10. Click Create.

5.2 Create a new service for MXNet with a custom placement strategy

In this step, you will create a new ECS Service that will ensure two instances of the MXNet container run at all times.

  1. In the navigation pane click Clusters.

  2. Click the cluster catsndogsECScluster.

  3. On the Services tab, click Create.

  4. In Configure service:

    1. In Launch Type, choose EC2.

    2. In Task definition, choose the latest revision for mxnet.

    3. In Cluster, choose catsndogsECScluster.

    4. In Service name, enter mxnetservice.

    5. In Number of tasks, enter 2.

    6. Leave Minimum healthy percent and Maximum percent at their defaults.

    You will now use a custom placement template to force the MXNet tasks to spread across Availability Zones, then across different instance types, and then BinPack based on Memory:

  5. In Placement Templates select Custom.

  6. In Type choose Spread, and in Field choose attribute:ecs.availability-zone.

  7. Click Add Strategy.

  8. In Type choose Spread, and in Field choose attribute:ecs.instance-type.

  9. Click Add Strategy.

  10. In Type choose BinPack, and in Field choose Memory.

  11. Click Next step.

  12. In Network configuration, for Load Balancing, choose Load balancer type of None.

  13. Click Next step.

  14. In Auto Scaling (optional), for Service Auto Scaling, choose Do not adjust the service’s desired count.

  15. Click Next step.

  16. Review the settings, and click Create Service.

  17. Click View Service.

5.3 Ensure the placement constraints are being honored

In this step, you will ensure that the constraint you configured for the mxnet task is being honored by the ECS service scheduler.

  1. In the navigation pane click Clusters.

  2. Click the catsndogsECScluster.

  3. Click the Tasks tab and locate one of the mxnet tasks from the list of running tasks.

  4. Click on the Task ID.

  5. In the Details view, locate and click on the EC2 instance id.

  6. The EC2 console will open and display the container instance.

  7. Check the Instance Type, it should be the type and size you selected in the earlier steps.

5.4 Add a container instance custom attribute using the AWS CLI, to control task placement for the cats service

In addition to the built-in attributes of instance type, AMI, availability zone and operating system type, you can also constrain the placement of tasks using custom attributes. A custom attribute is metadata added to container instances. Each attribute has a name, and an optional string value.

Management have asked that we enforce strict segregation between the cats and the dogs to stop the fighting with each other. In this task, you will use the AWS Management console to add a custom attribute to a container instance. The custom attribute will then be used to constrain the cats containers to a specific container instance.

In this step, you will use the AWS CLI to add a custom attribute to a container instance. You will then update the cats task to add a constraint using the custom attribute you created.

  1. Open to the AWS management console and open the Amazon ECS console at https://console.aws.amazon.com/ecs/.

  2. In the navigation pane click Clusters.

  3. Click the cluster catsndogsECScluster.

  4. Click the ECS Instances tab and copy a container instance ID from the Container Instance column.

  5. This step can be completed from your laptop. From the command prompt, run the following AWS CLI command. Replace <region> with your region, and <container_instance_id> with the instance ID you copied in the previous step:

    aws ecs put-attributes --cluster catsndogsECScluster --attributes "name=catslike,value=catnip,targetType=container-instance,targetId=<container_instance_id>" --region <your-region-name>

  6. You should see a response containing details of the attribute.

  7. In the navigation pane choose Task Definitions.

  8. Select cats from the list of task definitions.

  9. Click Create new revision.

  10. In Constraint, click Add constraint.

  11. Set the Expression to: attribute:catslike == catnip.

  12. Click Create.

Note: You can also try experimenting with some of the built-in attributes like instance type, AMI, availability zone and operating system type.

Verify that the custom attribute you created is visible in the console:

  1. Open to the AWS management console and open the Amazon ECS console at https://console.aws.amazon.com/ecs/.

  2. In the navigation pane click Clusters.

  3. Click the cluster catsndogsECScluster.

  4. Click the ECS Instances tab and select the check box for the container instance you added the custom attribute to.

  5. Click Actions and View/Edit Attributes.

  6. Verify the Catslike key exists and the value is Catnip.

  7. Click Close to return to the ECS Instances tab.

5.5 Update the cats service to use the custom attribute

In this step, you will update the cats service to use the new task definition you created in the previous step.

  1. In the navigation pane choose Clusters.

  2. Click the cluster catsndogsECScluster.

  3. Click the Services tab then click the cats service.

  4. Click Update.

  5. In Configure service:

    1. In Task definition, choose the task definition you created in the earlier step.

    2. In Cluster, choose the cluster catsndogsECScluster.

  6. Click Next step.

  7. In Load Balancing, choose Next step.

  8. In Service Auto Scaling (optional), click Next step.

  9. Review the settings, and click Update service.

  10. Click View Service.

5.6 Ensure the placement constraints are being honored

In this step, you will use the AWS management console to ensure that the constraint you configured for the cats task, is being honored by the ECS service scheduler.

  1. In the navigation pane choose Clusters.

  2. Click the cluster catsndogsECScluster.

  3. Click the ECS Instances tab and locate the instance with the Container Instance you added the custom attribute to in the earlier step.

  4. You should see that all cats tasks are now running on the container instance with the catslike attribute.

What’s Next

Automated Deployments