Re: [linux-lvm] Mapping LVs to physical device

["Stuart D. Gathman" <stuart bmsi com>]

On Tue, 30 Jun 2009, Chris Farey wrote:

> I have a requirement to be able to work out which areas of a physical device
> assigned to LVM are being used by various logical volumes. I haven't found any
> easy way to do this using an API, so I've resorted to spawning off lvm
> commands and interpretting the output.

It is also useful to go the other way: given a physical sector, figure out
which LV it is in and the offset.  When there is a physical disk error
(and no mirroring or such), it is useful to map it to an offset in a LV,
and then to a file.  Modern disks can "heal" themselves by writing over 
the sector (copying, repairing or replacing, and then overwriting the file).

-- 
	      Stuart D. Gathman <stuart bmsi com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
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