topic Re: FC60 - Sharing Logical Volumes in Operating System - HP-UX

FC60 - Sharing Logical Volumes

Patrick Graham — Wed, 06 Dec 2000 23:42:13 GMT

I am trying to see the same Volume Goup on two systems connected to an FC60.
Details:
I have two systems (PROD and DEV) connected to an FC60. I have configured 1 LUN from PROD and 2 LUNs from DEV. All LUNs are using LVM. In SAM, I can see the correct LUN number, description, and size from either system. If I am in SAM on PROD I can only see LVM info for PROD. SAM on PROD shows the LUN for DEV as unused. In SAM on DEV, I can see only the LVM info for DEV. SAM on DEV shows the LUN made on PROD as unused. I am trying to prepare for a failover, how do I get a VG as viewable by both systems? Sorry, no MC/SG!

Re: FC60 - Sharing Logical Volumes

Trevor Dyson — Thu, 07 Dec 2000 06:43:46 GMT

Hi,

LVM has no locking mechanism to ensure that Volume groups activated on two systems simultaneously are handled sanely. Activating a volume group on two systems can (and probably will) lead to data coruption or loss.

Check out this post for a fairly thorough discussion.

http://my1.itrc.hp.com/cm/QuestionAnswer/1,1150,0xd96c7e990647d4118fee0090279cd0f9!1,00.html

Re: FC60 - Sharing Logical Volumes

Stephen Doud — Tue, 12 Dec 2000 20:33:57 GMT

I requested an enhancement to the SAM group to teach SAM to be caustious about shared physical volumes (SR 8606104964). Currently, it simply cannot see that a disk is owned by another server.

Without MC/ServiceGuard, you are on your own protecting the data on the disks.

Re: FC60 - Sharing Logical Volumes

Patrick Graham — Tue, 12 Dec 2000 22:37:10 GMT

Trevor,
Thanks for the direction.
Answered all my questions!
Sincerely,
Patrick