Introduction of OpenStack Orchestration feature.

1. OpenStack Orchestration
(Heat)
Jimi Chen

2. Agenda
• What is Orchestration?
• Heat Architecture
• Heat Orchestration Template
• Autoscaling
• References

3. What is Orchestration?

4. What is Orchestration?
• Orchestration is a tool for orchestrating clouds that
automatically configures and deploys resources in stacks.
• The collection of resources associated with a template is
known as a stack, and resource type can be stack.
• Cloud infrastructure to be represented in a declarative form
(template).
• Orchestration can worked with AWS CloudFormation
templates and HOT(Heat Orchestration Template)
templates.

5. Heat Architecture

6. Heat Overview Diagram

7. Heat Architecture
• heat
- The heat tool is a CLI which communicates with the heat-api to
execute AWS CloudFormation APIs.
• heat-api
- The heat-api components provides an OpenStack-native REST
APIs that processes API requests by sending them to heat-
engine over RPC

8. • heat-api-cfn
- The heat-api-cfn components provides an AWS-style Query API
that is compatible with AWS CloudFormation and process API
requests by sending them to heat-engine over RPC.
• heat-engine
- The heat engine does the main work of orchestrating the launch
of templates and providing events back to the API consumer.

9. Heat Architecture

10. Heat Orchestration Template

11. Template Format
CFN
(CloudFormation)
JSON format
HOT
(Heat Orchestration Template)
YAML format

12. Template structure

13. Heat Template Version
• 2015-05-23
- support the functions listed in the
right hand.

14. Parameter Groups
• Specifying how the input parameters should be
grouped and the order to provide the parameters
in.

15. Parameters
• Specifying input parameters that have to be
provided when instantiating the template.

16. supported types
parameter example

17. constraints
constraints example

18. Resources
• Defines actual resources that make up stack
deployed from the HOT template
(for instance compute instances, networks,
storage volumes).
resource example

19. Resources dependencies
• Resource type can be stack template, so
templates can be composed into hierarchical
structure.

20. Nested Stack Templates

21. AutoScaling

22. Autoscaling Concept
• Metrics or user events drive scaling
• Metrics can includes CPU utilization, memory
utilization, may more as well as custom dimensions.
• Heat can register with Telemetry for callbacks on
alarm events.
• Telemetry tells Heat about alarm events and Heat
scales a group based on a policy decision to scale
up or down.

23. Autoscaling Resources
• OS::AutoScale::ScalingGroup
- A group that can scale an arbitrary set of heat resources.
• OS::AutoScale::ScalingPolicy
- Affects the number of scaling units in a group (+1, -10%, etc).
• OS::AutoScale::WebHook
- Creates a new web hook that can be used to execute a ScalingPolicy.
- Example
https://github.com/openstack/heat-templates/blob/master/hot/autoscaling.yaml

24. References
• OpenStack Orchestration
http://docs.openstack.org/admin-guide-cloud/orchestration.html
• Heat Wiki
https://wiki.openstack.org/wiki/Heat
• Heat Orchestration Template(HOT) specification
http://docs.openstack.org/developer/heat/template_guide/hot_spec.html#template-structure
• Heat AutoScaling
https://wiki.openstack.org/wiki/Heat/AutoScaling
• Heat templates github
https://github.com/openstack/heat-templates