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To: freebsd-questions@freebsd.org
Date: Sat, 09 Jun 2007 13:05:18 +0100
From: Dieter <freebsd@sopwith.solgatos.com>
Subject: USB disk and write cache
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How do you set a USB disk's write cache to write-through mode?

As far as I can tell, putting "hw.ata.wc=0" in loader.conf
only affects directly connected PATA/SATA disks, not disks
connected via a USB-to-*ATA bridge.

Perhaps via camcontrol?  But "camcontrol modepage da0 -l -v"
returns nothing.