Book Image

KVM Virtualization Cookbook

Book Image

KVM Virtualization Cookbook

Overview of this book

Virtualization technologies such as KVM allow for better control over the available server resources, by deploying multiple virtual instances on the same physical host, or clusters of compute resources. With KVM it is possible to run various workloads in isolation with the hypervisor layer providing better tenant isolation and higher degree of security. This book will provide a deep dive into deploying KVM virtual machines using qemu and libvirt and will demonstrate practical examples on how to run, scale, monitor, migrate and backup such instances. You will also discover real production ready recipes on deploying KVM instances with OpenStack and how to programatically manage the life cycle of KVM virtual machines using Python. You will learn numerous tips and techniques which will help you deploy & plan the KVM infrastructure. Next, you will be introduced to the working of libvirt libraries and the iPython development environment. Finally, you will be able to tune your Linux kernel for high throughput and better performance. By the end of this book, you will gain all the knowledge needed to be an expert in working with the KVM virtualization infrastructure.
Table of Contents (15 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Managing secrets


Libvirt provides an API to create, store, and use secrets. Secrets are objects that contain sensitive information such as passwords, that can be associated with different volume backend types. Recall from the Working with storage pools recipe, which we created an iSCSI pool and volume from a remote iSCSI target and used it as the image for a KVM guest. In production environments, more often than not iSCSI targets are presented with CHAP authentication. In this recipe, we are going to create a secret to be used with an iSCSI volume.

Getting ready

For this recipe, we are going to need the following:

  • A storage pool with an iSCSI-backed volume
  • The libvirt package

How to do it...

To define and list secrets with libvirt, perform the steps outlined here:

  1. List all available secrets:
root@kvm:~# virsh secret-list
 UUID Usage
-------------------------------------------------------------------
root@kvm:~#
  1. Create the following secrets definition:
root@kvm:~# cat volume_secret.xml
<secret ephemeral...