From owner-freebsd-hackers Sat Jun 21 10:49:07 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id KAA11501 for hackers-outgoing; Sat, 21 Jun 1997 10:49:07 -0700 (PDT) Received: from sendero-ppp.i-connect.net (sendero-ppp.i-Connect.Net [206.190.143.100]) by hub.freebsd.org (8.8.5/8.8.5) with SMTP id KAA11464 for ; Sat, 21 Jun 1997 10:48:55 -0700 (PDT) Received: (qmail 11650 invoked by uid 1000); 21 Jun 1997 17:49:01 -0000 Message-ID: X-Mailer: XFMail 1.2-alpha [p0] on FreeBSD Content-Type: text/plain; charset=iso-8859-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <199706200929.CAA12213@implode.root.com> Date: Sat, 21 Jun 1997 10:49:01 -0700 (PDT) Organization: Atlas Telecom From: Simon Shapiro To: dg@root.com Subject: Re: Announcement: New DPT RAID Controller Driver Available Cc: Brian Tao , FREEBSD-SCSI , FREEBSD-HACKERS , "Justin T. Gibbs" Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Hi David Greenman; On 20-Jun-97 you wrote: ... > Before everyone throws out their metal drive enclosures in favor of > plastic ones, let me say something about my experiance. Wcarchive used to > lose a couple of drives a month back when they were housed in plastic > enclosures. I noticed that the drives in that box ran hot, and I finally > got > tired of flying down to the Bay area so often to deal with it and > convinced > WC to replace the cabinet/enclosures with an all-steel one made by > Kingston. > This was about a year ago. Result: The drives run almost cold now and we > haven't had a single failure in that array since. All of our drives have > fairly well balanced spindles and don't vibrate all that much, and I've > never > seen a reported seek failure or noticed any slowness. In my opinion, the > all- > metal enclosure is a significant factor in the cooling of the drives and > these > days I wouldn't consider anything else. > YMMV. Before this turns into a religious war :-) IMHO; there is nothing inherently bad in platic carriers nor in metal carriers. Either technology can be either well made or poorly made. If David would have examined both the plastic carriers that failed and the metal carriers that are so successful, he would have discovered that one is allowing better air flow than the other. Should David had taped shut all the air passages in the metal carrier, it would have overheater just as nicely, unless the thing was imeresed in coold water. I brought up the platic carriers more as an anecdore to illustrate that platic is not necessarily bad, nor metal necessarily good. Good airflow, vibration isolation, quality drives, and just as important carriers rack and cabinet cooling are just as important. Simon