OK, so I have cleared everything off my /dev/sda (except, presumably, the MBR) and all is well still, Fedora still boots and my Windows guest virtual machine is still working.
How do I now set up /dev/sda using LVM? As I understand it the sequence is to create a Physical Volume using pvcreate, then a Logical Group that uses the Physical Volumes I have created and then I create a logical volume in the Logical Group.
The problem is that I don't understand how you tell pvcreate what disk it is to use. The 'synopsis' on the pvcreate man page says:-
SYNOPSIS pvcreate [-d|--debug] [-f[f]|--force [--force]] [-y|--yes] [-h|--help] [-t|--test] [-v|--verbose] [--labelsector] [-M|--metadatatypetype] [--metadatacopies#copies] [--meta- datasizesize] [--restorefilefile] [--setphysicalvolumesizesize] [--version] [-Z|--zeroy/n] PhysicalVolume [PhysicalVolume...]
Which doesn't seem to give much clue as to what disk it uses, PhysicalVolume is (as I understand it) the name that pvcreate gives to the chunk of disk you want to use, so what disk does it use?