Book Image

Hybrid Cloud for Developers

By : Manoj Hirway
Book Image

Hybrid Cloud for Developers

By: Manoj Hirway

Overview of this book

This book introduces you to the hybrid cloud platform, and focuses on the AWS public cloud and OpenStack private cloud platforms. It provides a deep dive into the AWS and OpenStack cloud platform services that are essential for developing hybrid cloud applications. You will learn to develop applications on AWS and OpenStack platforms with ease by leveraging various cloud services and taking advantage of PaaS. The book provides you with the ability to leverage the ?exibility of choosing a cloud platform for migrating your existing resources to the cloud, as well as developing hybrid cloud applications that can migrate virtual machine instances from AWS to OpenStack and vice versa. You will also be able to build and test cloud applications without worrying about the system that your development environment supports. The book also provides an in-depth understanding of the best practices that are followed across the industry for developing cloud applications, as well as for adapting the hybrid cloud platform. Lastly, it also sheds light on various troubleshooting techniques for OpenStack and AWS cloud platform services that are consumed by hybrid cloud applications. By the end of this book, you will have a deep understanding of the hybrid cloud platform and will be able to develop robust, efficient, modular, scalable, and ?exible cloud applications.
Table of Contents (16 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Developing HEAT orchestration templates


We discussed the OpenStack orchestration engine in Chapter 2, Exploring AWS Cloud. To recap, OpenStack provides an orchestration engine that can process a template and deploy the specified resources. The template is written in the YAML format.

A basic template that deploys a single VM using the key-pair named test-key and the image cirros is as follows:

heat_template_version:2015-04-30description:Simple template that deploys a VMresources:my_instance:type:OS::Nova::Serverproperties:key_name: test-key
      image: cirros

A typical HOT template has three sections: template version, description, and resources. The description is optional, however, it is a good practice to specify the details about a template that you write.

The set of resources that a template deploys together is called a stack.

Let's now discuss a complex scenario where we want to deploy two VM instances in a specific order. We want VM1 to be started and booted successfully, before VM2 attempts...