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Date: Mon, 7 Sep 2009 10:40:06 +0200
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Thread-Topic: ZFS and DMA read error
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From: "Daniel Eriksson" <daniel@toomuchdata.se>
To: <freebsd-questions@freebsd.org>
Cc: Mark Stapper <stark@mapper.nl>
Subject: RE: ZFS and DMA read error
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Mark Stapper wrote:

> Yeah, i did the long SMART selftest three times now, each of which it
> failed on the same LBA address.

I assume 'smartctl -a /dev/adX' reports that the read test failed at LBA
XXX something?

> Why would I want to clear my driver before I run these tests?

In this case it's not really clearing the drive you are aiming for, it
is to write to every sector. If you have a failed sector (which you do),
writing to it will force the drive firmware to remap the sector. As far
as I know, most drives will not remap an unreadable sector until it is
written to.

/Daniel Eriksson