Configuring Amazon ECS Linux container instances to receive Spot Instance notices - Amazon Elastic Container Service
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Configuring Amazon ECS Linux container instances to receive Spot Instance notices

Amazon EC2 terminates, stops, or hibernates your Spot Instance when the Spot price exceeds the maximum price for your request or capacity is no longer available. Amazon EC2 provides a Spot Instance two-minute interruption notice for terminate and stop actions. It does not provide the two-minute notice for the hibernate action. If Amazon ECS Spot Instance draining is turned onon the instance, Amazon ECS receives the Spot Instance interruption notice and places the instance in DRAINING status.

Important

Amazon ECS does not receive a notice from Amazon EC2 when instances are removed by Auto Scaling Capacity Rebalancing. For more information, see Amazon EC2 Auto Scaling Capacity Rebalancing.

When a container instance is set to DRAINING, Amazon ECS prevents new tasks from being scheduled for placement on the container instance. Service tasks on the draining container instance that are in the PENDING state are stopped immediately. If there are container instances in the cluster that are available, replacement service tasks are started on them.

Spot Instance draining is turned off by default.

You can turn on Spot Instance draining when you launch an instance. Add the following script into the User data field. Replace MyCluster with the name of the cluster to register the container instance to.

#!/bin/bash
cat <<'EOF' >> /etc/ecs/ecs.config
ECS_CLUSTER=MyCluster
ECS_ENABLE_SPOT_INSTANCE_DRAINING=true
EOF

For more information, see Launching an Amazon ECS Linux container instance.

To turn on Spot Instance draining for an existing container instance

  1. Connect to the Spot Instance over SSH.

  2. Edit the /etc/ecs/ecs.config file and add the following:

    ECS_ENABLE_SPOT_INSTANCE_DRAINING=true

  3. Restart the ecs service.

    • For the Amazon ECS-optimized Amazon Linux 2 AMI:

      sudo systemctl restart ecs

  4. (Optional) You can verify that the agent is running and see some information about your new container instance by querying the agent introspection API operation. For more information, see Amazon ECS container introspection.

    curl http://localhost:51678/v1/metadata