Attaching Extra Volumes to a VPS
Beyond a VPS's main disk, you can attach additional Volumes - independent block devices for cases where you want extra storage that isn't tied to the main OS disk's lifecycle (e.g. bulk data storage you might want to detach and reattach to a different VPS later, or keep separate from OS-disk backups/resizing).
Create a volume from the VPS's own page, specifying its size - it's provisioned in the same storage pool the VPS itself uses. Once attached, the guest OS sees it as a normal additional block device (partition and format it from inside the guest, same as adding a second disk to any real server).
Volumes currently apply to KVM guests only - LXC containers use the host filesystem directly and don't have an equivalent concept of an attachable virtual disk.