From owner-freebsd-hackers@FreeBSD.ORG Fri Aug 19 14:11:47 2005 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7F05416A41F for ; Fri, 19 Aug 2005 14:11:47 +0000 (GMT) (envelope-from bv@bilver.wjv.com) Received: from wjv.com (fl-65-40-24-38.sta.sprint-hsd.net [65.40.24.38]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3A43643D45 for ; Fri, 19 Aug 2005 14:11:45 +0000 (GMT) (envelope-from bv@bilver.wjv.com) Received: from bilver.wjv.com (localhost.wjv.com [127.0.0.1]) by wjv.com (8.12.11/8.13.1) with ESMTP id j7JEBawT055241 for ; Fri, 19 Aug 2005 10:11:36 -0400 (EDT) (envelope-from bv@bilver.wjv.com) Received: (from bv@localhost) by bilver.wjv.com (8.12.11/8.13.1/Submit) id j7JEBa6a055240 for freebsd-hackers@freebsd.org; Fri, 19 Aug 2005 10:11:36 -0400 (EDT) (envelope-from bv) Date: Fri, 19 Aug 2005 10:11:30 -0400 From: Bill Vermillion To: freebsd-hackers@freebsd.org Message-ID: <20050819141130.GB54150@wjv.com> References: <20050819120018.206B416A420@hub.freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050819120018.206B416A420@hub.freebsd.org> Organization: W.J.Vermillion / Orlando - Winter Park ReplyTo: bv@wjv.com User-Agent: Mutt/1.5.6i X-Spam-Status: No, score=-2.8 required=5.0 tests=ALL_TRUSTED autolearn=failed version=3.0.4 X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on bilver.wjv.com Subject: Re: Parking disk drive heads X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: bv@wjv.com List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Aug 2005 14:11:47 -0000 "Bits dont fail me now!" was what freebsd-hackers-request@freebsd.org muttered as he hastily typed this on Fri, Aug 19, 2005 at 12:00 : > 1. Re: Parking disk drive heads (Glenn Dawson) > Message: 1 > Date: Wed, 17 Aug 2005 12:47:32 -0700 > From: Glenn Dawson > Subject: Re: Parking disk drive heads > At 11:32 PM 8/16/2005, m.ehinger@ltur.de wrote: > >Hi, > >which is the correct way to park the hd head? > Seagate drives park the heads automatically when they are turned > off. As far as I know, this applies to other manufacturer's > drives as well. To which he replied: > Message: 2 > Date: Thu, 18 Aug 2005 08:14:47 +0200 > From: m.ehinger@ltur.de > Subject: Re: Parking disk drive heads > I don't want to park them on turn off. I want to park them > before a possible strong shock which could cause damage and > unpark them afterwards. The setups for parking heads pretty much went away when the move from MFM drive to ATA technology. And if your are worried about a shock that could damage the drive, you will probably lose your computer at the same time. Check the technical specs on current drives. You will see that most will handled well over 100G shocks when not running, and usually far over 20G in operational mode. Considering that 20G to the human body usually means death you aren't going to have to worry about losing drives to operating bumps unless you have a habit of dropping them in parachutes from airplanes. :-) I have ruined drives with a bad bump in the past - but those were MFM drives - and that happened in the mid-to-late 1980s. The first HDs I saw could withstand less than 1G in shipping so the 5.25" Shugart ST-505 drives - $25090 for 5MB [that is MegaByte] were shipped in foam padded boxes a bit larger than the drive, and these boxes were suspended by springs from the corners of a much larger shipping box - in the 18"x18" size category. IOW - unless you are running some early ATA drives, shocks when running are something you don't have to really worry about, unless you plan to shove the entire computer off the desk when it is running with the power on. Bill [The orignal post was in of freebsd-hackers Digest, Vol 126, Issue 5] -- Bill Vermillion - bv @ wjv . com