From owner-freebsd-questions@FreeBSD.ORG Sun Feb 6 11:25:08 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E009116A4CE for ; Sun, 6 Feb 2005 11:25:08 +0000 (GMT) Received: from smtp11.wanadoo.fr (smtp11.wanadoo.fr [193.252.22.31]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3490643D49 for ; Sun, 6 Feb 2005 11:25:08 +0000 (GMT) (envelope-from atkielski.anthony@wanadoo.fr) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf1102.wanadoo.fr (SMTP Server) with ESMTP id DE1801C00090 for ; Sun, 6 Feb 2005 12:25:06 +0100 (CET) Received: from pix.atkielski.com (ASt-Lambert-111-2-1-3.w81-50.abo.wanadoo.fr [81.50.80.3]) by mwinf1102.wanadoo.fr (SMTP Server) with ESMTP id B7C641C00084 for ; Sun, 6 Feb 2005 12:25:06 +0100 (CET) X-ME-UUID: 20050206112506752.B7C641C00084@mwinf1102.wanadoo.fr Date: Sun, 6 Feb 2005 12:24:53 +0100 From: Anthony Atkielski X-Priority: 3 (Normal) Message-ID: <1088851878.20050206122453@wanadoo.fr> To: freebsd-questions@freebsd.org In-Reply-To: References: <200502051745.25937.hindrich@worldchat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: Re: Leaving a Computer Running ? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: freebsd-questions@freebsd.org List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Feb 2005 11:25:09 -0000 Ted Mittelstaedt writes: TM> In a clean room or positive pressure network room, where there is TM> an extremely low level of dust, off-the-shelf computer fans will TM> last many years longer than fans in a typical home PC. What about filters? On my current FreeBSD server (not in a clean room, alas!), the fans that I installed have washable plastic filters, which removes part of the dust. I'd love to find disposable filters that capture more dust and can simply be tossed at regular intervals. Ideally, they wouldn't interfere with airflow too much, but I realize that catching all dust and maintaining airflow are almost mutually exclusive. Currently I have two 8-cm fans blowing directly past the disk drives, in order to keep them as cool as possible (not that the drives are that busy, but I'm trying to be prudent). TM> For PC's left on for long periods, they have a different problem TM> because disk drives that spin at full speed continuiously (as TM> server drives do, servers have power saving disabled on their TM> drives of course for obvious reasons) the disk will eventually TM> overheat in just about all the garden-variety case designs. TM> (you can fix this yourself of course, by adding more fans to TM> the cases) Once the drive overheats the lubrication migrates TM> out of the bearings and if the drive is turned off for more TM> than 6-8 hours, it cools down enough to the point that the drive TM> will never spin up again. Interesting! Have you actually had this happen? I've had drives fail on restart but not because they wouldn't spin up (as far as I know). I've had drives fail very quickly when I've packed too many of them into a single case (as in weeks or months). We needed the additional space and we were lucky to get the drives--asking for more fans or a better case or anything like that would have been an exercise in futility. -- Anthony