Heat is OpenStack's orchestration engine that enables you to deploy cloud applications based on Heat Orchestration templates that you create. These templates are also called HOT templates.
With a HOT template, you can create different OpenStack resource types such as instances, floating IPs, volumes, users, and so on. Templates also enable you to deploy advanced functionalities such as instance high availability, instance autoscaling, and nested stacks. Thus, with Heat, all OpenStack core projects could receive a larger user base. With templates, Heat provides a way for you to override the default resource implementation by using instead the parameters which are passed from the template to the engine.
Heat provides its services through a RESTful web services API. As with all OpenStack applications, Python WSGI interfaces are used and applications are configured together using Paste. The HTTP endpoints of the application are made up of pipelines of Web Server Gateway Interface (WSGI) middleware. Heat specifically uses two endpoints: Port 8004 for the Heat API and port 8000 for the Heat CloudFormation.
Heat's own configuration is controlled by the /etc/heat/heat.conf configuration file. At this time, no Solaris-specific configuration parameters exist in the primary Heat configuration file.
For more information about the Heat component, refer to the OpenStack community's Heat documentation.