Suppose you have an LVM volume /dev/vg0/mylv. You have presented this as a virtual disk to a virtualised or emulated guest system. During installation the guest system sees it as /dev/sda and partitions it into /dev/sda{1,2,5,6} and completes the installation. Now at some point you need to access those filesystems from within the host system, without running the guest system. fdisk sees these partitions just fine: # fdisk -l /dev/vg0/mylv Device Boot Start End Blocks Id System /dev/vg0/mylv1 2048 684031 340992 83 Linux /dev/vg0/mylv2 686078 20969471 10141697 5 Extended /dev/vg0/mylv5 686080 8290303 3802112 83 Linux /dev/vg0/mylv6 8292352 11980799 1844224 83 Linux However, the devices such as /dev/vg0/mylv1 do not actually exist. I guess that because they're within an LV, the OS does not recognise this type of nesting by default. Is there any way I can prod Linux so that /dev/vg0/mylv1 or equivalent appears and thus becomes mountable within the host system? I understand that it's possible with qemu-nbd, and will use this if necessary. However, I was hoping for something more direct if possible, rather than simulating a network block device and attaching that.