Book Image

Containers in OpenStack

Book Image

Containers in OpenStack

Overview of this book

Containers are one of the most talked about technologies of recent times. They have become increasingly popular as they are changing the way we develop, deploy, and run software applications. OpenStack gets tremendous traction as it is used by many organizations across the globe and as containers gain in popularity and become complex, it’s necessary for OpenStack to provide various infrastructure resources for containers, such as compute, network, and storage. Containers in OpenStack answers the question, how can OpenStack keep ahead of the increasing challenges of container technology? You will start by getting familiar with container and OpenStack basics, so that you understand how the container ecosystem and OpenStack work together. To understand networking, managing application services and deployment tools, the book has dedicated chapters for different OpenStack projects: Magnum, Zun, Kuryr, Murano, and Kolla. Towards the end, you will be introduced to some best practices to secure your containers and COE on OpenStack, with an overview of using each OpenStack projects for different use cases.
Table of Contents (17 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Walk-through


In this section, we will walk you through how a container is created in Zun and how the request flows from the user to the Docker which creates the container. Zun interacts with multiple other OpenStack services for resources needed for the container.

The request flow for creating a container in Zun is as follows:

  1. The user sends a REST API call to the zun-api service for creating a cluster via a CLI or Horizon, with the authentication token received from KeyStone.
  2. zun-api receives the request and sends the request for the validation of token and access permission to KeyStone.
  3. KeyStone validates the token and sends updated authentications headers with roles and permissions.
  4. zun-api then parses some parameters from the request, such as the security group, memory, and runtime, and validates them.
  5. The requested network is created by zun-api. zun-api sends a request to Neutron to ensure the requested network or port is usable. If not, zun-api sends another request to Neutron to search...