[linux-lvm] Debugging partial drive failure

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

On Thu, 5 Jul 2007, Stuart D. Gathman wrote:

> On Wed, 4 Jul 2007, Jim Schatzman wrote:
> 
> > I made the mistake of trying to use pvmove to move any good data from a bad
> > disk to a new identical good disk in an LV. Unfortunately, the Pvmove failed
> > in midoperation. It cannot now be aborted, presumably because of the bad
> > disk.
> 
> I wish there was a SMART command to a drive that would tell it to pretend a
> range of sectors is bad until further notice (without actually remapping said
> sectors).  This would be a great help is debugging the error handling of
> things like LVM.  In fact, maybe there already is such a feature in SMART,
> and it just isn't widely known.

This could be added to the linux disk driver.  There could be an
option for a disk module that would pretend that a range of sectors
got an I/O error from the drive.  This would allow debugging the LVM
layer.

E.g. modprobe.conf:

options mptbase debug_bad=450000-500000

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