Book Image

OpenStack Essentials - Second Edition

By : Dan Radez
Book Image

OpenStack Essentials - Second Edition

By: Dan Radez

Overview of this book

OpenStack is a widely popular platform for cloud computing. Applications that are built for this platform are resilient to failure and convenient to scale. This book, an update to our extremely popular OpenStack Essentials (published in May 2015) will help you master not only the essential bits, but will also examine the new features of the latest OpenStack release - Mitaka; showcasing how to put them to work straight away. This book begins with the installation and demonstration of the architecture. This book will tech you the core 8 topics of OpenStack. They are Keystone for Identity Management, Glance for Image management, Neutron for network management, Nova for instance management, Cinder for Block storage, Swift for Object storage, Ceilometer for Telemetry and Heat for Orchestration. Further more you will learn about launching and configuring Docker containers and also about scaling them horizontally. You will also learn about monitoring and Troubleshooting OpenStack.
Table of Contents (20 chapters)
OpenStack Essentials Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Troubleshooting Nova launching instances


Nova has good logging and will most likely have a pretty good error message to indicate what is going wrong if you have trouble getting instances to launch. You would want to check logs for nova-api, nova-conductor, and nova-scheduler on the control tier, and on each compute node where there is a nova-compute service running. Let's look at what each of these agents does so that you know where to look when something is going wrong.

When a Nova command is executed, it talks to the nova-api service. If an error is received directly when a Nova command is executed, this is generally where you can find more detail beyond the immediate error message returned.

Once a command to act on an instance is accepted into the Nova infrastructure, there are two services that handle passing actions to the compute nodes – nova-scheduler and nova-conductor. Nova-scheduler is just what its name suggests. It handles the decision-making as to where to schedule resources across...