One of the core principles behind the design of Amazon ECS is the separation of the scheduling logic from the state management. This allows you to use the Amazon ECS schedulers, write your own schedulers, or integrate with third party schedulers. In this session we will explore the advanced cluster management capabilities of Amazon ECS and dive deep into the Amazon ECS Service Scheduler, which supports long-running applications by monitoring container health, restarting failed containers, and load balancing across containers. We will explain how you can communicate with the Amazon ECS API in order to integrate your own custom schedulers. We will then walk through how we built an Apache Mesos scheduler driver that enables you to integrate Mesos scheduling frameworks to work with Amazon ECS without requiring a Mesos cluster. We will also demo using Marathon to schedule Docker containers on an Amazon ECS cluster.

1. © 2016, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Chad Schmutzer, AWS Solutions Architect
October 24th, 2016
Scheduling Containers on
Amazon ECS

3. What is Amazon ECS?
Amazon EC2 Container Service (ECS) is a highly scalable,
high performance container management service. You
can use Amazon ECS to schedule the placement of
containers across your cluster. You can also integrate your
own scheduler or third-party scheduler to meet business
or application specific requirements.

4. Agenda
Container Management
Scheduling
Benefits
Demo

5. Container Management

6. Maintains Available Resources
Tracks Resource Changes
Accepts Resource Requests
Guarantees Accuracy and Consistency
What is a Container Manager?

7. CPU
Memory
Ports
Disk Space
Disk IOPS
Network Bandwidth
Resources

8. ECS
Agent
Docker
Task
Container Instance
Container
ECS Agent
Task
Container

9. Instance Registration
register-container-instance --total-resources
[
{
“name” : “cpu”,
“type” : “integerValue”,
“integerValue” : 2048
},
…
]

10. Modifying Exposed Resources

11. Accepting Resource Requests

12. Tasks
Shared Data Volume
Containers
launch
Container
Instance
Volume Definitions
Container Definitions

13. Starting a Task
API
User /
Scheduler
StartTask

14. Starting a Task
API
User /
Scheduler
StartTask
Cluster Management Engine

15. Starting a Task
API
User /
Scheduler
StartTask
Cluster Management Engine
Agent Communication

16. Starting a Task
API
User /
Scheduler
StartTask
Cluster Management Engine
Agent Communication
Docker
Container Instance
ECS Agent
Task
Container
WebSocket

17. Starting a Task
API
User /
Scheduler
StartTask
Cluster Management Engine
Agent Communication
Docker
Task
Container Instance
Container
ECS Agent
Task
Container
SubmitStateChange

18. Tracking Resource Changes

19. Terminated Task
API
User /
Scheduler
StartTask
Cluster Management Engine
Agent Communication
Docker
Task
Container Instance
Container
ECS Agent
SubmitStateChange

20. Missing Container Instance
API
User /
Scheduler
StartTask
Cluster Management Engine
Docker
Task
Container Instance
Container
ECS Agent
?
Agent Communication

21. Terminated Container Instance
API
User /
Scheduler
StartTask
Cluster Management Engine
Agent Communication
Termination
Notifier
Docker
Task
Container Instance
Container
ECS Agent

22. Guaranteeing Accuracy and
Consistency

23. Amazon ECS under the Hood
IDN-1 IDN IDN+1 IDN+2 IDN+3 IDN+4 IDN+5
IDN+6
IDN+5
WRITE
READ

24. Amazon ECS under the Hood
IDN-1 IDN IDN+1 IDN+2 IDN+3 IDN+4 IDN+5
IDN+6IDN+3
IDN+5IDN+2
WRITE WRITE
READREAD

25. Schedulers

26. What is a Scheduler?
Determine Desired State
Check Against Current State
Perform Action

27. ECS Schedulers
Batch Jobs
ECS Task scheduler
Run tasks once
Batch jobs
RunTask (random)
StartTask (placed)
Long-Running Apps
ECS Service scheduler
Health management
Scale-up and scale-down
AZ aware
Grouped Containers

28. Custom Schedulers
1. Calls the ECS List* and Describe* API operations to
determine the current state of the cluster.
2. Selects one (or more) container instances according to
the logic implemented.
3. Calls StartTask API to start a task on the selected
container instance.

29. Integration with third party schedulers
ECS allows you to use third party schedulers, e.g.
Marathon and Chronos
Integration via ECS API
For Mesos schedulers, the ECSSchedulerDriver interprets
the command given when scheduling jobs with Mesos and
starts a task with TaskDefinition family:revision

30. Amazon ECS Service Scheduler

31. Discovering Differences
Deployment Status Desired Pending Running
ecs-svc/1 PRIMARY 5 0 0
Minimum Healthy Maximum Healthy
50% 200%

32. Steady State
Determine
Placement Options
Deploy Task
Service State Machine
RUNNING == DESIRED
RUNNING != DESIRED &&
STATUS == PRIMARY
ALL_RUNNING < MAX_HEALTHY

33. Discovering Differences
Deployment Status Desired Pending Running
ecs-svc/2 PRIMARY 10 0 0
ecs-svc/1 ACTIVE 5 0 5
Minimum Healthy Maximum Healthy
50% 200%

34. Steady State
Determine
Placement Options
Deploy Task
RUNNING == DESIRED
RUNNING != DESIRED &&
STATUS == PRIMARY
ALL_RUNNING < MAX_HEALTHY
Service State Machine
Clear Deployment Kill Task
ALL_RUNNING >
MAX_HEALTHY
RUNNING != DESIRED &&
STATUS == ACTIVE

35. Other Considerations
ELB Registration/Deregistration
Permissions and Errors
Task Health
Scale Down Requests

37. Multiple Schedulers

38. Amazon ECS – Scheduling

39. Amazon ECS – Scheduling

40. Amazon ECS – Scheduling

41. Amazon ECS – Scheduling

42. Demo

43. © 2016, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
All attendees will receive a special giveaway gift!
Please join us for the
AWS DevDay Networking Reception
5:00 - 6:30 PM
JW Grand Foyer

44. Thank You!

45. Don’t Forget Evaluations!