TIP: It is possible to use LVM on top of an iSCSI storage. That way
you get a 'shared' LVM storage.
+Thin provisioning
+~~~~~~~~~~~~~~~~~
+
+A number of storages, and the Qemu image format `qcow2`, support _thin
+provisioning_. With thin provisioning activated, only the blocks that
+the guest system actually use will be written to the storage.
+
+Say for instance you create a VM with a 32GB hard disk, and after
+installing the guest system OS, the root filesystem of the VM contains
+3 GB of data. In that case only 3GB are written to the storage, even
+if the guest VM sees a 32GB hard drive. In this way thin provisioning
+allows you to create disk images which are larger than the currently
+available storage blocks. You can create large disk images for your
+VMs, and when the need arises, add more disks to your storage without
+resizing the VMs filesystems.
+
+All storage types which have the 'Snapshots' feature also support thin
+provisioning.
+
+
Storage Configuration
---------------------