I had a rather full 700GB LVM... full of all my most critical everything.

Anyway, for some reason, all the metadata went poof, and when I recreated the volume group, it showed all my drives as empty (though they really aren't)

There has to be a way to get the data off the drives?!? Maybe a way to force the lvm2 usespace tools to check the data on the drives and rebuild its metadata?

OH NO! I'm so frantic.

Do you have a burner in your machine, if you do I would recommend downloading the latest Knoppix. Knoppix is a complete operating system that boots and runs from a cdrom. If you can still read the data from the hard drive, you can use the burning software K3B to backup the important data, basically use it as a recue disc.

Well, I still have a perfectly functioning OS on the machine.

It is deeper than that, because I had a reiserfs partition within an lvm partition, spanned across four drives.

I need one of two things:
- Program that does a raw sector read of the array and reconstructs the lvm portion of the hard drives
- Sector offset so I can try to use dd to read the hard drive in raw sector mode to an image, but ignoring the beginning of the drive

Sorry, can't help there, that's way out of my league. I've never messed around with LVM before

I suggest that you ask on the LVM mailing list and not touch the system at all until you have LVM working again.

As a shot-in-the-dark answer, and I don't really recommend you try it, maybe it would work if you did the requisite "pvcreate /dev/foo" commands, then the vgcreate (those two steps you've already taken), then the lvcreate's in the same order with the exact same logical volume sizes as when you created it in the first place. If you just recreate the volume group, the logical volumes still won't be recreated. But I have no idea whether it would keep the proper physical layout of logical volumes to correspond to the filesystem that's already on the disks. I kind of doubt it would damage your chances of recover any more than recreating just the volume group did, but I don't know enough about LVM to be sure.

I managed to successfully recreate the volume group, and it doesn't show as empty, but I can't mount the filesystem either. It says it is a fubared superblock, but none of the reiser tools actually make it work.