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Message-ID: <54184016.7060208@interlog.com>
Date: Tue, 16 Sep 2014 09:50:14 -0400
From: Douglas Gilbert <dgilbert@interlog.com>
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To: Bram Vandoren <bram.vandoren@ster.kuleuven.be>, freebsd-scsi@freebsd.org
Subject: Re: How to disable hard disk write cache?
References: <541804B0.7070407@gmail.com> <5418311A.3080007@ster.kuleuven.be>
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On 14-09-16 08:46 AM, Bram Vandoren wrote:
> On 09/16/2014 11:36 AM, Xu Zhe wrote:
>
>> Does anyone knows how to disable write cache of hard disk?
>
> Have a look at camcontrol modepage and the WCE bit.

You could also use the sdparm utility:
    sdparm -c WCE <device>