Você precisa ter espaço livre no seu HD
Exemplo
# fdisk /dev/sda
Command (m for help): p
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes, 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000a3dd7
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 4196351 2097152 83 Linux
/dev/sda2 4196352 172148735 83976192 8e Linux LVM
CREATE NEW PARTITION
Command (m for help): n
Partition type:
p primary (2 primary, 0 extended, 2 free)
e extended
Select (default p): p
Partition number (1-4, default 3):
Using default value 3
First sector (172148736-1953525167, default 172148736):
Using default value 172148736
Last sector, +sectors or +size{K,M,G} (172148736-1953525167, default 1953525167):
Using default value 1953525167
Partition 3 of type Linux and of size 849.4 GiB is set
ESCREVA
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
# partprobe
CRIAR VOLUME FÍSICO
# pvcreate /dev/sda3
Physical volume "/dev/sda3" successfully created
EXIBIR VOLUME FÍSICO
# pvdisplay
--- Physical volume ---
PV Name /dev/sda2
VG Name fedora_fed18
PV Size 80.09 GiB / not usable 4.00 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 20501
Free PE 1
Allocated PE 20500
PV UUID 1BWm7E-M3Z8-WFJQ-vLRI-eUqa-MfPm-6x2mef
"/dev/sda3" is a new physical volume of "849.43 GiB"
--- NEW Physical volume ---
PV Name /dev/sda3
VG Name
PV Size 849.43 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID xo8Xrp-MpKE-MVE1-fkJr-Hebe-NSwo-4w502f
CRIE UM GRUPO DE VOLUME
# vgcreate virtual-machines /dev/sda3
Volume group "virtual-machines" successfully created
MOSTRAR VOLUMEN GROUP
# vgdisplay
--- Volume group ---
VG Name virtual-machines
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 1
Act PV 1
VG Size 849.42 GiB
PE Size 4.00 MiB
Total PE 217452
Alloc PE / Size 0 / 0
Free PE / Size 217452 / 849.42 GiB
VG UUID M69gwe-S5e9-1ZXM-zlxg-L3yc-pR0P-mhW6Vi
--- Volume group ---
VG Name fedora_fed18
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 80.08 GiB
PE Size 4.00 MiB
Total PE 20501
Alloc PE / Size 20500 / 80.08 GiB
Free PE / Size 1 / 4.00 MiB
VG UUID r0LXYG-BQdo-WN7w-GcPa-uKxE-68mC-li3HFm
E, EM SEGUIDA, CRIE OS VOLUMENS LÓGICOS (para ser usado como o disco virtual da DomU) DENTRO DO SEU GRUPO DE VOLUMES
EXEMPLO (crie um grupo de vaolume de 50G para sua máquina centos virual)
lvcreate -nfedora64-1 -L50G /dev/virtual-machines
Logical volume "fedora64-1" created
:)
Alex Dávila