Book Image

Mastering KVM Virtualization

Book Image

Mastering KVM Virtualization

Overview of this book

A robust datacenter is essential for any organization – but you don’t want to waste resources. With KVM you can virtualize your datacenter, transforming a Linux operating system into a powerful hypervisor that allows you to manage multiple OS with minimal fuss. This book doesn’t just show you how to virtualize with KVM – it shows you how to do it well. Written to make you an expert on KVM, you’ll learn to manage the three essential pillars of scalability, performance and security – as well as some useful integrations with cloud services such as OpenStack. From the fundamentals of setting up a standalone KVM virtualization platform, and the best tools to harness it effectively, including virt-manager, and kimchi-project, everything you do is built around making KVM work for you in the real-world, helping you to interact and customize it as you need it. With further guidance on performance optimization for Microsoft Windows and RHEL virtual machines, as well as proven strategies for backup and disaster recovery, you’ll can be confident that your virtualized data center is working for your organization – not hampering it. Finally, the book will empower you to unlock the full potential of cloud through KVM. Migrating your physical machines to the cloud can be challenging, but once you’ve mastered KVM, it’s a little easie.
Table of Contents (22 chapters)
Mastering KVM Virtualization
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

How to enable nested KVM?


By default, nested KVM is disabled.

Open /etc/modprobe.d/kvm.conf as root user using a text editor like vim. If the file does not exist create /etc/modprobe.d/kvm.conf:

  • #Uncomment kvm_intel line if your CPU make is Intel

  • #options kvm_intel nested=1

  • #Uncomment kvm_intel line if your CPU make is AMD

  • #options kvm_amd nested=1

Save the file and reboot the system. Once the system reboots verify nested by checking.

# cat /sys/module/kvm_intel/parameters/nested
Y

For AMD, the file to check is /sys/module/kvm_intel/parameters/nested:

Fig - 1

After verifying nested status, change the CPU model of the VM to match host's CPU; that is, enable Copy host CPU configuration (Fig-1). Start the VM and execute egrep '(vmx|svm)' /proc/cpuinfo in the VM. You should be able to see vmx or svm in the output based on the host CPU model.

Your VM can now create its own virtual machines for the purpose of testing.