Re: BUG: Files corrupt after moving LVM volume to USB disk

From: Alasdair G Kergon
Date: Thu Mar 22 2007 - 11:59:32 EST


On Wed, Mar 21, 2007 at 06:15:47PM +0200, Marti Raudsepp wrote:
> >On Tue, Mar 20, 2007 at 12:34:08PM +0200, Marti Raudsepp wrote:
> >lvmove
> >> wouldn't move the partition back to /dev/sda5 after "defragmenting" it.)

> However, when attempting to move back the LV, the allocater can create two
> extents, but the "mirror" LVM target does not appear to support regions that
> are continuous on one copy and fragmented on another.

This is entirely a user-space restriction, and a fix is finally on the
cards.

> I even tried explicitly specifying --alloc= to lvmove, and it didn't have
> any
> effect, confirming that it's not about allocation, but likely the "mirror"
> stage of the move.

The workaround is to instruct 'pvmove' how to break up the move into two
or more pieces by specifying ranges of Physical Extents on the command
line (see man pages). E.g. /dev/sdc:10000-19999:30000-

Alasdair
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