Creating PVGs

[Cliff Lim Kok Hwee]

Gd Day Forum,

I am creating a few PVGs on a new Volume Group
i) vgcreate -p 64 -s 8 -e 10000 -g pvg0901 /dev/vg09 /dev/dsk/cxxxxxx
ii) vgextend -g pvg09P02 /dev/v09 /dev/dsk/cxxxxx

Query: Please advise whether the above mentioned steps are applicable?

I would want to create a Logical Volume on vg09, with the -D y option

lvcreate -D y -r N -s g -L /dev/vgsg1

Query: Will extent striping be performed automatically on all the PVs in PVG pvg0901 then if no space available will then extent striping on the PVs in PVG pvg0902? I presume this should be the case.

Thanks/cliff

[Leif Halvarsson_2]

Hi,
Use pvcreate to "initialize" a physical volume for use in a volumegroup.
Use vgcreate for creating a NEW volumegroup.
Use vgextend for adding a physical volume to an EXISTING volumegroup.

I am not sure I understand the last query but, a locical volume can NEVER spawn across volumegroupsbut, (if using the -D option) spawn across all avialable physical volumes in a group.

[Devender Khatana]

Hi Cliff,

What you are doing is absolutely right only. Onlything is that you should target paths of all devices in your first command on which you want to create pvg0901.

With -D option you are also specifying -s g that means two copies of a Physical extent can not share the same PVG. Also -D options means one PE of each Physical Volume Group will be allocated once & 2nd PE will be allocated to 2nd PVG. For doing this you must have more than one PVG in your Physical Volume Group.


HTH,
Devender

[Keith Bryson]

Hi Cliff

You can create the VGs as normal, then edit the /etc/lvmpvg file and tailor your PVGs as you like them (see 'man /etc/lvmpvg'). This avoids the confusing command lines with the vgcreate.

Keith

[TwoProc]

Cliff,

You're on the right track for creating the PVG.

I think the striping will occur only across a single PVG. It will not go automatically to the next one.