From owner-freebsd-scsi Wed Jun 5 22:55:14 1996 Return-Path: owner-freebsd-scsi Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id WAA05362 for freebsd-scsi-outgoing; Wed, 5 Jun 1996 22:55:14 -0700 (PDT) Received: from okjunc.junction.net (root@okjunc.junction.net [199.166.227.1]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id WAA05345; Wed, 5 Jun 1996 22:55:10 -0700 (PDT) Received: from sidhe.memra.com (sidhe.memra.com [199.166.227.105]) by okjunc.junction.net (8.6.11/8.6.11) with SMTP id WAA28368; Wed, 5 Jun 1996 22:10:56 -0700 Date: Wed, 5 Jun 1996 22:54:18 -0700 (PDT) From: Michael Dillon To: Dror Matalon cc: freebsd-scsi@FreeBSD.ORG, freebsd-isp@FreeBSD.ORG Subject: Re: ERROR info:747d9d asc:11,0 Unrecovered read error, other SCSI issues In-Reply-To: Message-ID: Organization: Memra Software Inc. - Internet consulting MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-scsi@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Wed, 5 Jun 1996, Dror Matalon wrote: > Quantum XP34300W 4.3 Fast Wide SCSI drives on a pentium 133 > as our news machine. News servers eat drives. No matter what type of drive, they just wear out and die. > 2. My number 1 frustration with FreeBsd/Unix on a PC is related to > the number of SCSI errors that we're running into. We might be at > fault for not running the computer room cool enough, Computer room??? How about the case where the drives are? Most clone cases have NO (that's zero) airflow engineering done. The only way to be sure that the drives are running cool enough (especially 7200 RPM drives) is to mount them with space in between (an inch or so) and mount extra fans that blow air across the top of the drive. When you open the case and remove the bad drive, stick your finger on top. If it burns so badly that it blisters, you need more cooling. Even if it's only hot, add more airflow anyway. > recently started using Granite's custom made SCSI cables. Still > we've had close to 20% mortality rate on our SCSI disks. Are other > people also experiencing these kind or problems? Almost everybody who runs news servers. Go into your machine room any time day or night and you hear drives rattling constantly. Go put your ear against the news server, that's the one that NEVER stops rattling. The others actually go in fits and starts. It helps to really cool things down a lot, i.e. air conditioned machine room that you need to put on a sweater when you go in. It also helps to use RAID (http://www.mylex.com DAC960SI) because it lessens the physical activity on any one drive to some extent. And the special fans to blow air across the top of each individual drive. The nice thing about a DAC960 is that with a proper hot-swap chassis and RAID 5, replacing a drive doesn't shut anything down. Michael Dillon ISP & Internet Consulting Memra Software Inc. Fax: +1-604-546-3049 http://www.memra.com E-mail: michael@memra.com