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

64
VG Version 2.1
VG Max Size 8t
VG Max Extents 1048576
--- Logical volumes ---
LV Name /dev/vg1/lvol1
LV Status available/syncd
LV Size (Mbytes) 307168
Current LE 38396
Allocated PE 76792
Used PV 2
--- Physical volumes ---
PV Name /dev/disk/disk46
PV Status available
Total PE 38396
Free PE 0
...
PV Name /dev/disk/disk47
PV Status available
Total PE 38396
Free PE 0
Online reprovisioning in combination with DLE
In the previous examples, for a volume group with two PVs, you increased the LUN sizes from 200
GB to 300 GB, increased the maximum VG size from 500 GB to 8 TB, and increased the logical
volume size from 204784 MB to 307168 MB. Now, you want to increase the maximum VG size
even further, from 8 TB to 128 TB. However, because there are no free extents left at the ends of the
two physical volumes, you must perform online reprovisioning in combination with DLE. To do this,
you first expand the LUNs from 300 GB to 400 GB, and then perform online reprovisioning in
combination with DLE to increase the maximum VG size to 128 TB.
1. Run online vgmodify in review mode.
# vgmodify -r -a -S 128t vg1
vgmodify: Error: Cannot reconfigure physical volume
"/dev/disk/disk46" to the
requested maximum volume group size 134217728 MB without moving
extent(s). The last 30 extent(s) have to be made free
(see pvmove(1M)) to be able to reconfigure the physical volume.
The physical volume "/dev/disk/disk46" can be reconfigured to the
new maximum volume group size 11884952 MB without removing free
extents from the end of the physical volume.
Physical volume "/dev/disk/disk46" was not changed.
vgmodify: Error: Cannot reconfigure physical volume
"/dev/disk/disk47" to the
requested maximum volume group size 134217728 MB without moving
extent(s). The last 30 extent(s) have to be made free
(see pvmove(1M)) to be able to reconfigure the physical volume.
The physical volume "/dev/disk/disk47" can be reconfigured to the
new maximum volume group size 11884952 MB without removing free
extents from the end of the physical volume.
Physical volume "/dev/disk/disk47" was not changed.
You cannot increase the maximum volume group size from 8 TB to 128 TB without either
shrinking the logical volume or increasing the LUN sizes further with a DLE.
2. Run a storage utility to expand the LUNs from 300 GB to 400 GB.
3. Verify the increases LUN size.