xen2 ~ # vgremove aoe
  /dev/aoe/test2: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/debian: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/test: read failed after 0 of 4096 at 0: Input/output error
  /dev/cdrom: open failed: Read-only file system
  Attempt to close device '/dev/cdrom' which is not open.
  /dev/aoe/test2: read failed after 0 of 4096 at 4294901760: Input/output error
  /dev/aoe/test2: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/debian: read failed after 0 of 4096 at 4294901760: Input/output error
  /dev/aoe/debian: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/test: read failed after 0 of 4096 at 4294901760: Input/output error
  /dev/aoe/test: read failed after 0 of 4096 at 0: Input/output error
  Volume group "aoe" not found
xen2 ~ # ls /dev/aoe
debian  test  test2
xen2 ~ # ls /dev/aoe
xen2 ~ # vgdisplay
  /dev/aoe/test2: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/debian: read failed after 0 of 4096 at 0: Input/output error
  /dev/aoe/test: read failed after 0 of 4096 at 0: Input/output error
  No volume groups found