I have sometimes done this with Linux VM's that I use for local development.
Usually, the VM disk images are some where between the need to backup Applications and configuration files, and not as important my work and data files.
The problem with VM's is not just the quantity of data that needs to be backed up, but the overall size of the data that needs to be evaluated. I think that CrashPlan does a pretty good job of just coping the changed data of the disk image, but it has to do a HUGE amount of processing with every backup. Therefore VM's are hard to fit in with the remote versioned backups of CrashPlan and Arq.
I do backup these up via Carbon Copy Clone when I mirror the entire drive.
> Why not just setup backups from inside the VM's, while having the base VM image backed up somewhere (once) as well?
That would be quite a project, compared with backing up everything on the host system as I do now.
I have all sorts of VMs. Some of them are extremely minimal OSes (think router/firewall distros). I have no idea how I would be able to back these up from inside the VM. And even for the VMs where I could do that, why bother? It seems like a lot of work.
By having an extremely fast sector backup running on my host system, I can be sure that all of my VMs are backed up, with no extra effort when I install a new one. I don't have to worry about how I would do a "restore" in any of those specific VMs, I can just restore files on the host OS and know that it will work perfectly.
