How to fix error “volume group holds max 1 physical volume(s)” for system VG

By default the system volume group holds only one disk. If you tried to add another disk then you might be received like below error.

Existing space in system volume group

# vgs
  /dev/cdrom: open failed: No medium found
  VG     #PV #LV #SN Attr   VSize  VFree  
  applvg   1   1   0 wz--n- 40.68G 692.00M
  system   1   7   0 wz--n- 19.88G      0 

Error while trying to extend the system VG

# vgextend system /dev/sdb1
  /dev/cdrom: open failed: No medium found
  No space for '/dev/sdb1' - volume group 'system' holds max 1 physical volume(s).
  Unable to add physical volume '/dev/sdb1' to volume group 'system'.

Change the system VG value

# vgchange system -p 0
  Volume group "system" successfully changed

Now extending of system VG is successful

# vgextend system /dev/sdb1
  Volume group "system" successfully extended

Now you can notice in vgs and pvs that disk has been successully added to VG and PV.

# vgs
pv  VG     #PV #LV #SN Attr   VSize  VFree  
  applvg   1   1   0 wz--n- 40.68G 692.00M
  system   2   7   0 wz--n- 29.19G   9.31G

# pvs
  PV         VG     Fmt  Attr PSize  PFree  
  /dev/sda2  system lvm2 a--  19.88G      0 
  /dev/sdb1  system lvm2 a--   9.31G   9.31G
  /dev/sdb2  applvg lvm2 a--  40.68G 692.00M