How to extend VG conf when reach to MAX PV 16 ?

[Worapoj P.]

Dear all,

Please help me. How to extend the maximan number of PV in VG configuration and what is the maximan size of file system which can be allocated. Right now in some VG, it have 16 PVs . Can I additional some PV to this VG?

Notes my env is HP-UX 11.00 running on N4000.

Best Regards,
Worapoj P.

[Stefan Farrelly · Accepted solution]

Sorry, no way to increase max PV once the VG is created. You will have to backup your data, destroy the VG, recretae it with an increased PV then reload your data.

[James R. Ferguson]

Hi:

Not only can you not increase the Max PV, but you also can't increase the Max PE per VG after creation of the VG. The default value for Max PV is 16. The default value for Max PE per VG is 1016 or the size of the largest volume at creation time. You must unload your data, recreate the VG from scratch, and reload. If it's any consolation, I ran into both limitations trying to extend the total size of a database whose growth requirments had been grossly mis-specified.

...JRF...

...JRF...

[Rick Garland]

Sounds like you are on some kind of disk farm and database grouping is within one VG.

Unless you created the VG to have more than 16 PV (the default), there is not much you can do except backup data and recreate the VG with greater than 16 PV. Another option would be to create another VG with a similar name.

The vgcreate command you would be looking for is vgcreate -p (max_pv). The maximum PVs in a VG is 255.

[Worapoj P.]

Dear all,

Thank you very much for your help.

Best Regards,

[Wodisch]

Hi,
it seems like you should not only increase the max PV, but also the PE size
parameter! Use vgcreate like:
vgcreate -p 128 -l 32 -s 64 -e 1024 /dev/vgXX /dev/dsk/cXtYdZ ...

That will allow up to 128 disks, eacho of up to 1024 * 64MB in the VG, used
as up to 32 LVs - you are going for a few big LVs, right?
See Bill Hassel's opinion on that in the attachment...
HTH,
Wodisch

[Wodisch]

Hi,
it seems like you should not only increase the max PV, but also the PE size
parameter! Use vgcreate like:
vgcreate -p 128 -l 32 -s 64 -e 1024 /dev/vgXX /dev/dsk/cXtYdZ ...

That will allow up to 128 disks, eacho of up to 1024 * 64MB in the VG, used
as up to 32 LVs - you are going for a few big LVs, right?
See Bill Hassel's opinion on that in the attachment...
HTH,
Wodisch