What is the concept and working principle of Heat in icehouse version

This article shows you the concept and working principle of Heat in the icehouse version, which is concise and easy to understand. It will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.

Introduction to Heat

Heat is the main project that OpenStack is responsible for planning. It can be based on the template to achieve the initialization of resources in the cloud environment, dependency processing, deployment and other basic operations, but also can solve the automatic contraction, load balancing and other advanced features. At present, Heat's own template format (HOT) is constantly improving, and it also supports AWS CloudFormation templates (CFN). The goal of HOT is to completely replace CFN in the near future.

Heat provides an OpenStack native REST API and CloudFormation compatible query API.

How Heat works

Heat mainly manages the application based on the template file, which can define the resources needed by the application. Resources can include a variety of types (CFN and the resource types supported by HOT may be different), such as IP, network, image, user, instance and so on. When defining resources, you can also specify the dependencies between resources. For example, when you create an instance using cloud disk, you can specify that you must create a cloud disk when creating an instance.

After editing the template file, you can use the template file to create a Stack. During the creation process, the Heat engine will call the corresponding resource plug-in to create resources according to the resources defined in the template file. After the Stack is created, Heat can manage the life cycle of all resources in the Stack, for example, you can delete resources, or update the definition of resources in Stack by updating templates.

The simple principles of Heat are as follows:

The execution logic of the Heat engine is roughly as follows:

What can Heat do now?

Heat is still young compared to other OpenStack projects (such as Nova), and attention should start with the H version, so it may still have many shortcomings. The following is a simple list of features supported in the I version

Support for HOT,CFN template format

The resource types in HOT have been greatly expanded in the Icehouse version.

The above is the concept and working principle of Heat in the icehouse version. Have you learned the knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.