Introduction to Heat Architecture and how autoscaling implemented using Heat & Ceilometer

1. Openstack Heat & How Autoscaling works
@Openstack chennai meetup Aug 2015
Jayaprakash
Technical Lead, Product Development
jayaprakash.r@cloudenablers.com
Beny Raja
Technical Lead, DevOps
benyraja.j@cloudenablers.com

2. Overview
● Heat is the orchestration component of Openstack.
Template-driven engine that allows us to describe
and automate the deployment of infrastructure &
application
● Extended capabilities such as Nested stacks,
Resource Groups, Auto scaling, Software
deployment using configuration management tools
like puppet

3. Services
● Heat - CLI which communicates with heat-api
● Heat-api - REST based service which sends api
requests to heat-engine via RPC
● Heat-engine - Orchestrates openstack resources
● Heat-api-cfn - REST based service which sends
api requests to heat-engine via RPC

4. Heat Architecture

5. HOT Template structure
● heat_template_version
● description
● parameter_groups
● parameters
● input
● resources
● output
Reference:
http://docs.openstack.org/developer/heat/template_guide/hot_spec
.html

6. HOT Template

7. Develop your own Resource Plugins
● Plugin Life cycle –
Create,Update,Suspend,Delete,Resume
● Registering resource plugin name –
OS::Nova::Workload
● Properties & Attributes
● Handler Methods – handle_create, handle_update,
handle_delete...
● Configure heat to register new plugins and restart
heat-engine service
Reference:
http://docs.openstack.org/developer/heat/pluginguide.html

8. Heat - Standalone Mode
● Orchestrate Multi openstack setups
● Standalone mode configuration in heat.conf
○ [paste_deploy]
flavor = standalone
○ [authpassword]
multi_cloud = true
allowed_auth_uris =
http://192.168.1.171:5000/v2.0,
http://192.168.1.223:5000/v2.0
● Heat cli to access remote openstack
heat --os-no-client-auth --os-username admin --os-password
openstack --os-tenant-name admin --os-auth-url
http://192.168.1.223:5000/v2.0 --heat-url
http://192.168.1.10:8004/v1/98073903698740af87fb57ca9e41eed5

9. Autoscaling
● To maintain application availability and allows you
to scale the capacity up or down automatically
according to conditions you define
● Automatically increase the number of instances
during demand spikes to maintain performance
● Heat & Ceilometer are the components used to
implement Autoscaling in Openstack

10. Autoscaling workflow

11. Ceilometer Alarm Resource

12. Autoscaling Group Resource
lb_server.yaml

13. Alarm Action URL
● Heat engine server address
● Stack id & name
● Scaling resource id & name
● URL params – Timestamp, Signature, Access key
http://192.168.1.142:8000/v1/signal/arn:openstack:heat::<stack_id
>:stacks/test_stack/<resource_id>/resources/scaleup_policy?Time
stamp=&SignatureMethod=HmacSHA256&AWSAccessKeyId=fa7
1fad02e974f4f8a21265c58bacf0f&SignatureVersion=2&Signature=
poYnVLF9mLEGjBXbjT63svjCnymnhrLP9chFPHiyVoo%3D

14. References
● http://docs.openstack.org/developer/heat/template
_guide/hot_spec.html
● https://wiki.openstack.org/wiki/Heat
● https://github.com/openstack/heat-templates
● https://wiki.openstack.org/wiki/Heat/Blueprints/heat
-multicloud
● http://developer.openstack.org/api-ref-
orchestration-v1.html

15. Thank You