Installation guide

Removing Physical Volumes from a Volume Group
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# vgscan
Reading all physical volumes. This may take a while...
Found volume group "new_vg" using metadata type lvm2
Found volume group "officevg" using metadata type lvm2
4.3.6. Removing Physical Volumes from a Volume Group
To remove unused physical volumes from a volume group, use the vgreduce command. The
vgreduce command shrinks a volume group's capacity by removing one or more empty physical
volumes. This frees those physical volumes to be used in different volume groups or to be removed
from the system.
Before removing a physical volume from a volume group, you can make sure that the physical volume
is not used by any logical volumes by using the pvdisplay command.
# pvdisplay /dev/hda1
-- Physical volume ---
PV Name /dev/hda1
VG Name myvg
PV Size 1.95 GB / NOT usable 4 MB [LVM: 122 KB]
PV# 1
PV Status available
Allocatable yes (but full)
Cur LV 1
PE Size (KByte) 4096
Total PE 499
Free PE 0
Allocated PE 499
PV UUID Sd44tK-9IRw-SrMC-MOkn-76iP-iftz-OVSen7
If the physical volume is still being used you will have to migrate the data to another physical volume
using the pvmove command. Then use the vgreduce command to remove the physical volume:
The following command removes the physical volume /dev/hda1 from the volume group
my_volume_group.
# vgreduce my_volume_group /dev/hda1
4.3.7. Changing the Parameters of a Volume Group
The vgchange command is used to deactivate and activate volume groups, as described in
Section 4.3.8, “Activating and Deactivating Volume Groups”. You can also use this command to
change several volume group parameters for an existing volume group.
The following command changes the maximum number of logical volumes of volume group vg00 to
128.
# vgchange -l 128 /dev/vg00
For a description of the volume group parameters you can change with the vgchange command, see
the vgchange(8) man page.