[libvirt-users] VM running with storage image file deleted

[Michael Hierweck]

On 10.01.19 11:19, Roosen, Nicolas wrote:
> Hello, I have a strange issue I'd like to have some insights on.
> 
> 
> We have 2 running VM, the storage pool is over NFS. Unfortunately, the backend storage folder has been deleted (so the image file in it as well, obviously) ...
> 
> 
> Yet, the 2 VM are still up and running, with their root filesystem being mounted "rw".
> 
> 
> - how does that work? I was expecting that with the file image being deleted, the VM would not work at all.

The file was "unlinked" but still exists.

https://superuser.com/questions/283102/how-to-recover-deleted-file-if-it-is-still-opened-by-some-process

I would consider doing a backup from inside the VM, too.

> - since the VM is still running, is there a way to create a snapshot of it in order to re-create the image file on another storage pool ? I'm currently exploring "virsh snapshot-create-as ...", but if access to the image file is needed, it will fail.

Note: the file will be lost, when it is released by the QEMU process.