topic Re: max number of lvol's in Operating System - HP-UX

max number of lvol's

Christian Marquardt_1 — Tue, 05 Jul 2005 03:27:27 GMT

Hello,
I've a database with rawdevice datafiles on a hp/ux 11.0 machine.
I've heared the max number of lvol's in a volume group I can create is 255. Is this right?
Has anyone an idea how can I decrease the number of raw's containing oracle datafiles?
Is there any way to create more than 255 lvol's in a volume group or a second volumegroup?

kind regards
Christian

Re: max number of lvol's

Bernhard Mueller — Tue, 05 Jul 2005 03:36:15 GMT

Christian,

255 lvols is max per VG, if you need more, you need a new VG. For a new VG you need new disks/LUNs.

you only option is to consider using larger lvols, I assume the all have a 2GB size currently, so talk to your DBA about using larger rlvols if you have plenty of space in your VG but are running out of lvols.

vgdisplay will tell you the basics.

Regards,
Bernhard

Re: max number of lvol's

Mahesh Kumar Malik — Tue, 05 Jul 2005 03:42:19 GMT

Hi

For more then 255 lvols, you can create second volume group

Regards
Mahesh

Re: max number of lvol's

Christian Marquardt_1 — Tue, 05 Jul 2005 03:45:23 GMT

Hi Bernhard,
I'm the dba ;-)
I understand what you say.
My problem is, that the Db is a high available production DB and I cant shutdown it for a long time and recreate all the datafiles.
I'm looking for a good way to migrate the "old" 2 GB raws to larger raws (maybe 16 GB). Right now I have not found any good way to do this.

Kind regards
Christian

Re: max number of lvol's

Victor_101 — Wed, 06 Jul 2005 00:09:41 GMT

hi
255 is the max lvols that is available on a vg.. full stop...
as for your migration path , i suggest you get new drives and plug in ( i suppose you are using a disk storage system of some sort, maybe SAN) create luns and present to the system , this time size your rvols properly.. i fortunately realised this limitation in my migration phase and planned my rvols so i did not need more than 255 rvols per vg. simply arrange the large and small rvols across the vgs evenly so that this limitation does not catch up with you.
as per one of ur original queries, y reduce the number or rvols?? it doesnt hurt to have max number set even if ur not using..

victor

Re: max number of lvol's

Cem Tugrul — Wed, 06 Jul 2005 00:15:36 GMT

Hi,
From here it looks you need 2nd Vg with
large LUN...
Also please have a look at the attachment...
Good Luck,