From owner-freebsd-questions Thu Sep 12 12:57:23 2002 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 896CE37B400 for ; Thu, 12 Sep 2002 12:57:20 -0700 (PDT) Received: from idk.com (idk.com [65.104.9.99]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2C94143E6A for ; Thu, 12 Sep 2002 12:57:20 -0700 (PDT) (envelope-from tony@idk.com) Received: (from tony@localhost) by idk.com (8.9.3/8.9.3) id MAA01634; Thu, 12 Sep 2002 12:57:16 -0700 (PDT) From: Tony Message-Id: <200209121957.MAA01634@idk.com> Subject: Re: Backups on IDE disks To: freebsd-questions@freebsd.org, ahl@austclear.com.au Date: Thu, 12 Sep 2002 12:57:16 -0700 (PDT) In-Reply-To: <200209120417.OAA23587@tungsten.austclear.com.au> from "Tony Landells" at Sep 12, 2002 02:17:22 PM X-Mailer: ELM [version 2.5 PL6] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG SCSI drives are designed to be hot (with power on) swapped. They are used used a most of the servers and such, replace a drive if one begins to fail. There is no reason for them to powered up all the time, just power or insert the one you want to use and on latestest versions of FreeBSD there is a command to rescan the SCSI bus for changed. I have been doing the poswer off/on sequence one both a tape drive and drive for years. You might get a kernel error or so when you first try to use it, but it does work. If one were to remove the drive that had the termination for the SCSI bus on it, that can generate problems. Having one or more devices (depending on the number you have) on or off, things are designed to work. An big advantage for SCSI. Most errors have either to do with inferior cable or termination. > > Hi Tony, > > Firstly, this isn't my query so responding to me doesn't have > much value. > > Secondly, all SCSI devices on a chain should be powered on at > all times. Powering off any device on the chain can result in > bus problems. > > Or at least that's the theory. In many cases I have gone along > quite happily for ages before I started getting mysterious errors > from a SCSI device, only to find on closer inspection that either > the bus wasn't terminated or there was a device in the chain that > had never been powered on. > > > tony@idk.com said: > > You could even mount the SCSI drive in a SCSI remobable drive slot and > > take the drive or swap it to anyother. > > That's much more likely to be trouble-free, since it's the intended > use :-) > > Tony > -- > Tony Landells > Principal Networks, Security & IT Systems Engineer Ph: +61 3 9677 9319 > Australian Clearing Services Pty Ltd Fax: +61 3 9677 9355 > Level 4, Rialto North Tower > 525 Collins Street > Melbourne VIC 3000 > Australia > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message