Striped and Distributed LV

[Fabrizio Maggioni_2]

Hi,

I would like to know if i can change a Logical Volume striped to distributed one.
If yes, can you suggest me the procedure to follow.(I know that to configure a distributed LV i need to configure before the PVG)

Thanks a Lot.
Fabrizio

[Steven E. Protter · Accepted solution]

Shalom,

Change it?

No.

Build a new one and copy your data to it? Yes.

SEP

[Fabrizio Maggioni_2]

OK

[Gurumanickam]

hi fabrizio,
find the following step for Creating PVGs - Physical Volume Groups
DocId: LVMKBRC00005089 Updated: 10/16/02 8:04:00 AM
PROBLEM
I need to ensure that the mirrored extents of a Logical Volume can always be established on a disk not connected to the same card.
CONFIGURATION
HP-UX 10.x, 11.x
RESOLUTION
Systems with mirrored logical volumes often use multiple SCSI controllers to be able to work on in case of hardware failure. To secure that the mirrored extents of a logical volume can always be established on a disk not connected to the same card, PVGs - Physical Volume Groups can be created:
# vgcreate -g [PVG name] vgXY /dev/dsk/cCtTdA /dev/dsk/cCtTdB ...
All stated physical volumes are part of the new PVG.
Further PVGs for an existing volume group can be created or extended by using the vgextend command.
The information of the Physical Volume Group is stored in the ASCII file /etc/lvmpvg. This file can also be created or extended manually, instead of using the vgcreate and vgextend commands. lvmpvg stores the volume-group information for all of the physical volume groups in the system. The information is stored in a hierarchical format. First, it starts with a volume group under which multiple physical volume groups can exist. Under each physical volume group, a list of physical volumes can be specified. There must be at least one physical volume group in each volume group that appears in this file. The physical-volume-group name must be unique within the corresponding volume group, although it is permissible to use a common physical volume group name across different volume groups. There can be as many volume groups in this file as there are in the system.
At following example of /etc/lvmpvg, four hard disks are connected to two SCSI controllers.
# cat /etc/lvmpvg

VG /dev/vg01
PVG scsi0
/dev/dsk/c0t6d0
/dev/dsk/c0t5d0
PVG scsi1
/dev/dsk/c1t2d0
/dev/dsk/c1t1d0
The volume group shows up as follows:
# vgdisplay -v /dev/vg01

...
--- Physical volume groups ---
PVG Name scsi0
PV Name /dev/dsk/c0t6d0
PV Name /dev/dsk/c0t5d0
PVG Name scsi1
PV Name /dev/dsk/c1t1d
PV Name /dev/dsk/c1t2d0
The allocation policy of the logical volumes has to be set to PVG-strict , so that the extents are allocated automatically to a disk within the other PVG when mirroring:
# lvchange -s g /dev/vg01/lvol4

[Fabrizio Maggioni_2]

thanks.