Vgmodify For A Version 2.X Volume Group - HP -UX 11i Administrator's Manual

# vgdisplay vg32
--- Volume groups ---
VG Name
VG Write Access
VG Status
Max LV
Cur LV
Open LV
Max PV
Cur PV
Act PV
Max PE per PV
VGDA
PE Size (Mbytes)
Total PE
Alloc PE
Free PE
Total PVG
Total Spare PVs
Total Spare PVs in use
VG Version

vgmodify for a Version 2.x Volume Group

If the maximum volume group size (chosen when the Version 2.x volume group was created by
the vgcreate command) needs to be increased, then the vgmodify -S option can be used to
increase the maximum volume group size
For instance, the maximum volume group size might need to be increased to allow more extents
to be added to the volume group through the vgextend command or through LUN expansion
(see the vgmodify -E option described
The maximum volume group size can also be reduced through the vgmodify -S option to make
more extents available on the physical volumes.
Increasing the maximum volume group size might require that additional space be added to every
physical volume through LUN expansion. In this case, you can invoke the E and S options
together to handle the LUN expansions and increase the maximum VG size in a single step.
LVM might also use free extents at the ends of the physical volumes to increase the maximum
volume group size. If insufficient free extents are available at the end of some physical volumes,
and those physical volume cannot be expanded further via LUN expansion, it might be necessary
to free the extents at the ends of those physical volumes by using the pvmove command to relocate
the portions of the logical volumes that are using those extents.
When using the vgmodify -S option to increase the maximum volume group size, note that the
maximum volume group size is not increased until all physical volumes in the volume group are
reconfigured.
When using the vgmodify -S option to decrease the maximum volume group size, note that the
maximum volume group size is decreased prior to reconfiguring the physical volumes.
To increase the maximum size of a Version 2.x volume group, follow these steps:
1. Use the vgmodify review mode to verify that there is enough free space on all of the physical
volumes to reconfigure them to the desired larger maximum VG size. The vgmodify command
checks for free extents at the ends of the PVs that it can utilize, and also checks for free spaces
resulting from prior LUN expansions. You must provide the -E option and the -S option for
review mode to check for LUN expansions. It might be necessary to use the pvmove command
to relocate the portions of logical volumes residing at the ends of the PVs.
# vgmodify -r -a -E -S 64t vg1
62 Administering LVM
/dev/vg32
read/write
available
255
0
0
255
2
2
15868
4
32
1084
0
1084
0
0
0
1.0
in"Modifying Physical Volume Characteristics" (page 77)).