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

Troubleshooting the virtualization layer of OpenStack


KVM is the de facto hypervisor choice for OpenStack compute as service. There are plenty of native KVM debugging mechanisms that you can use for troubleshooting issues that occur while launching an instance on your OpenStack environment. Alternatively, if something unusual suddenly happened with a critical instance, libvirt and QEMU provide a rich set of debugging controls that allow us to query (or modify) the state of virtual machines in distress.

The following log files play a very important role in troubleshooting compute layer issues. Please note these files are on the nova compute hosts nodes:

/var/log/nova/nova-api.log
/var/log/nova/nova-compute.log
/etc/libvirt/qemu/*.xml
/var/lib/nova/instances/*
/var/lib/libvirt/qemu/

/var/lib/libvirt/qemu/ is the directory where QEMU creates a log file for each instance or VM that was started on the node. If there is an I/O problem faced by the instance, or storage performance is degraded,...