vgdisplay没有显示信息,不知道是何原因，如何解决

Question

root@bogon /]# fdisk -l
Disk /dev/sda: 80 GiB, 85899345920 bytes, 167772160 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
Disklabel type: dos
Disk identifier: 0x5737e8b0

Device     Boot    Start       End  Sectors  Size Id Type
/dev/sda1  *        2048    616447   614400  300M 83 Linux
/dev/sda2         616448   4810751  4194304    2G 82 Linux swap / Solaris
/dev/sda3        4810752  41943039 37132288 17.7G 83 Linux
/dev/sda4       41943040 104857599 62914560   30G 83 Linux


[root@bogon /]# pvdisplay
  "/dev/sda4" is a new physical volume of "30.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sda4
  VG Name               
  PV Size               30.00 GiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               Muvhp7-eOWx-0pB1-PK8D-HLXK-nt9c-fzYb53
   
[root@bogon /]# vgdisplay
[root@bogon /]#