The Book of Xen

Enlarge Your Disk

Both file-backed images and LVM disks can be expanded transparently from the dom0. We're going to assume that disk space is so plentiful that you will never need to shrink an image.

Be sure to stop the domain before attempting to resize its underlying filesystem. For one thing, all of the user-space resize tools that we know of won't attempt to resize a mounted filesystem. For another, the Xen hypervisor won't pass along changes to the underlying block device's size without restarting the domain. Most important, even if you were able to resize the backing store with the domain running, data corruption would almost certainly result.

File-Backed Images

The principle behind augmenting file-backed images is simple: We append more bits ...