LVM Volume Group Dynamic LUN Expansion (DLE) and Contraction (DLC) (September 2009)

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shows that you can increase the VGRA to 896 KB without using the –n argument or 4096 KB
(the PE size) with –n. The list of settings is based upon a VGRA no greater than 896 KB in
size.
2. Run vgmodify in review mode. There are two optimal settings that allow a 23 GB disk to be
part of the volume group with at least 19 physical volumes. The following example uses a
max_pv of 19.
# vgmodify -r -p 19 -e 5628 vg02 #offline mode
or
# vgmodify -r -a -p 19 -e 5628 vg02 # online mode
Volume Group configuration for /dev/vg02 has been saved in
/etc/lvmconf/vg02.conf
Current Volume Group settings:
Max LV 255
Max PV 16
Max PE per PV 5119
PE Size (Mbytes) 4
VGRA Size (Kbytes) 736
The current and new Volume Group parameters differ.
An update to the Volume Group IS required
New Volume Group settings:
Max LV 255
Max PV 19
Max PE per PV 5628
PE Size (Mbytes) 4
VGRA Size (Kbytes) 896
Review complete. Volume group not modified
The review mode (-r) displays the current and new settings for comparison. The program
completes before making any changes.
3. Apply the changes using the same vgmodify arguments but without –r.
For offline mode, d
eactivate the volume group and run vgmodify without the –a option.
# vgchange –a n vg02 # For offline mode only
Volume group "vg02" has been successfully changed.
# vgmodify -p 19 -e 5628 vg02 #Offline mode
or
# vgmodify -a -p 19 -e 5628 vg02 #Online mode
Current Volume Group settings:
Max LV 255
Max PV 16
Max PE per PV 5119
PE Size (Mbytes) 4
VGRA Size (Kbytes) 896
The current and new Volume Group parameters differ.
An update to the Volume Group IS required
New Volume Group settings:
Max LV 255
Max PV 19
Max PE per PV 5628
PE Size (Mbytes) 4