topic Re: PVG Concept in Operating System - HP-UX

PVG Concept

Cliff Lim Kok Hwee — Fri, 17 Dec 2004 23:09:40 GMT

Gd Day Forum,

Currently, my existing system running HP-UX 11.00 has a volume group vg02 and all its logical volumes are equally striped across 6 harddisks.

Query: Correct me if I am wrong, if there is a need for additional space eg. due to a need to extend a filesystem, I will have to add in 6 new harddisks all together? Do I term this as extent based striping?

Query: Can the creation of PVG volume group help to eliminate the cons I mentioned above?

thanks n regards/cliff

Re: PVG Concept

bhavin asokan — Fri, 17 Dec 2004 23:40:27 GMT

hi,

pvg is used at the time of mirroring.if you are mirroring with two pvg ,it will make you sure that your filesystem is on one set of disks(1st PVG disks) and its mirror is on other set of disks(2nd pvg disks).
you can get information by searching itrc forum with keyword PVG.

see the following links

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=33822

http://forums1.itrc.hp.com/service/forums/parseCurl.do?CURL=%2Fcm%2FQuestionAnswer%2F1%2C%2C0x437142308663d611abdb0090277a778c%2C00.html&admit=716493758+1103344382044+28353475

regds,

Re: PVG Concept

Cliff Lim Kok Hwee — Sat, 18 Dec 2004 00:14:49 GMT

Hi Guys,

Query: Read the articles, does it mean that PVG is related to mirroring and does not have any relations to logical volume striping which I had mentioned?

Query: If that is the case, while creating a volume group of eg 4 harddisks/LUNs for logical volume striping which run on XP storage, do I need to check out the harddisks/LUNs information to verify whether that can be LV striped in a volume group?

I presume I dun think there is a need.

Thanks for the advise/cliff

Re: PVG Concept

Phillip Renner — Sat, 18 Dec 2004 16:41:53 GMT

The answer to the first question is yes, you need 6 more disks to extend a file system thats striped across 6 disks. As for PVG We use it for striping and mirroring var, opt and usr in vg00. it allows us to easily (maybe easier is the right word) stripe vg00 disks. I doubt that it helps us much but we need all the speed we can get. If you already have mirror-ux installed I wouldn't use PVG anywhere but in vg00..

Re: PVG Concept

Cliff Lim Kok Hwee — Sun, 19 Dec 2004 04:53:10 GMT

Gd Day Forum,

Correct my understanding based on your replies, if I have a PVG volume group and all its logical volumes are equally striped across 6 harddisks, and a need arises for additional space, do I also need to add in 6 harddisks?

Thanks n regards/cliff