Run an ECS Fargate task running `sleep` and exec into the task. This can be used to get a Linux shell in a subnet without launching an EC2 instance.

ecs-fargate-sleep-task.sh

# Prerequisites:
# - ECS Fargate cluster
# - ECS task IAM role: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-iam-roles.html
#   Be sure to include ECS exec permissions: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-iam-roles.html#ecs-exec-required-iam-permissions
# - (optional) ECS task execution IAM role: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task_execution_IAM_role.html


aws ecs list-task-definitions

# Register a task definition for alpine image running "sleep 600" so you can exec into the container for 10 min

aws ecs register-task-definition --cli-input-json '{
  "family": "alpine-sleep",
  "cpu": "1024",
  "memory": "2048",
  "containerDefinitions": [{
    "name": "alpine",
    "image": "public.ecr.aws/docker/library/alpine",
    "cpu": 512,
    "memory": 1024,
    "command": ["sleep", "600"]
  }],
  "taskRoleArn": "arn:aws:iam::111111111111:role/ecs-task",
  "executionRoleArn": "arn:aws:iam::111111111111:role/ecs-task-execution",
  "networkMode": "awsvpc",
  "runtimePlatform": {
      "cpuArchitecture": "X86_64",
      "operatingSystemFamily": "LINUX"
  },
  "requiresCompatibilities": [
      "EC2",
      "FARGATE"
  ]
}'

# Run a task referencing the task definition created above

aws ecs run-task \
  --cluster cluster-name \
  --task-definition alpine-sleep \
  --network-configuration '{
    "awsvpcConfiguration": {
      "subnets": ["subnet-aaaaaaaa", "subnet-bbbbbbbb"],
      "securityGroups": ["sg-cccccccc"],
      "assignPublicIp": "DISABLED"
    }
  }' \
  --capacity-provider-strategy 'capacityProvider=FARGATE_SPOT' \
  --enable-ecs-managed-tags \
  --enable-execute-command

# Note the task id, or find the new running task in ECS console

aws ecs execute-command \
  --cluster cluster-name \
  --task '<taskid>' \
  --interactive \
  --command /bin/sh

# A shell will open on the task container, and you can run commands here. The task will die after 10 min as specified in the task definition