topic Re: vgimport with clariion cx600 in Operating System - HP-UX

vgimport with clariion cx600

Kevin Liquori_1 — Thu, 14 Oct 2004 07:53:09 GMT

I've been mounting BCVs from my Symmetrix to my HP-UX hosts using the BCV split/vgimport process for years without any problem. Now I'm trying to achieve the same results with a Clariion CX600 using SnapClones. I sync the drives and them fracture (split) them. When I try and do a vgimport I receive the error:

Physical Volume "/dev/dsk/c32t0d3" contains no LVM information

I'm sure I have the correct drive. The source disk is a mirrored LUN (200GB usable, 400GB raw) the target SnapClone is a non-mirrored LUN (200GB usable, 200GB raw). Dell, the reseller of this unit, told me:

1) The source and target sizes must be identical in their raw form (400GB in this case)
2) All I/O to the source must be halted - I have to unmount the filesystem from the source host.

The scenario in which I would use these drives would be for Oracle databases. On the Symmetrix I normally place the database in hotbackup mode and split it off without unmounting the filesystem.

Attached is a listing of the SnapClone states while sync'd and split. Does anyone else have experience with a Clariion and HP-UX?

TIA...Kevin

Re: vgimport with clariion cx600

Kevin Liquori_1 — Thu, 14 Oct 2004 07:53:59 GMT

Sorry, forgot to add the attachment.

Kevin

Re: vgimport with clariion cx600

Geoff Wild — Thu, 14 Oct 2004 10:08:38 GMT

I have no experience with Clarion - a lot with EMC/bcv's.

It does not sound like the bcv's are setup correctly.

Can you run any symmir commands?

I would like to see the output of:

symmir -g yourdevicegroup query

Rgds...Geoff

Re: vgimport with clariion cx600

Lee Cockrell — Thu, 14 Oct 2004 10:23:26 GMT

First off, I believe the most likely cause of the problem is with LVM and the disk labels. But since I know more about the Clariion side I will concentrate there.

How are you mounting the clones? Back to the original host? If it is a different host, did you set initiator type and failover mode? Are you using Powerpath or PVLinks with the Clariion?

It looks like the Clariion mirroring and fracturing went fine, as long as you unmounted the filesystems first.

Re: vgimport with clariion cx600

Sundar_7 — Thu, 14 Oct 2004 13:14:49 GMT

Kevin,

LVM doesnt care about whether your LUN is hardware mirrored or not. LVM cannot understand hardware mirroring either.

So, effectively the LUN size visible to the source host and the backup host should be of same size. LUN mirrored/not mirrored at the hardware side doesnt really matter for successful vgimport.

I havent worked on SnapClones. But I would check the sync/split proces.

Check the LVM headers in the disk

# echo "0x2008?4D" | adb /dev/dsk/c32t0d3

Post the output from the above command.

- Sundar.

Re: vgimport with clariion cx600

Kevin Liquori_1 — Tue, 19 Oct 2004 10:13:44 GMT

I finally figured this out. When you create a clone group on the Clariion (similar to a BCV device group) there's an option to sync the drives upon creation. Initially I didn't use this option but ran the commands manually afterward. It wouldn't work as I discussed above, so I recreated the clone group with this option enabled and now it works. Very strange.

Unfortunately the symmir commands don't work on the Clariion. They have their own set of equivalent commands which are almost as good, but not quite.

Thanks, everyone, for your assistance!