Hello
This new HowTo explains how to backup a VM without powering it down. It's specifically aimed at KVM although it may work with any virtualization software that uses Linux as the host.
Please review it and let me know what you think, particularly if you are already doing something similar yourself, or would like to. Do you have answers to any of the questions in the 'Questions' section?
It has not been released yet and it's a first draft, so break it to me gently... http://wiki.centos.org/HowTos/BackupKVMGuest
(The article's internal Wiki links are broken - not sure what's going on there, but ignore that)
A taster...
1. Introduction
This article explains how to backup a virtual hard disk to a remote location, even while it is use.
One advantage of running software in a virtual machine is that the entire disk can be backed up in one go, including Operating System, software, configuration files, registry, permissions, data and all. Re-establishing a system after a failure is therefore quicker and more reliable than re-installing software and restoring data.
The method employs LVM to take a snapshot of the guest disk and then uses rsync to update changes to a previous backup on a remote server. If there is a database server on the guest then it is flushed & locked at the point the snapshot is taken. This method came into use around 2008 following wider availability and awareness of virtualization software, cheaper faster network bandwidth, and cheaper bigger disks. ...
Thanks, Julian