From owner-freebsd-questions@FreeBSD.ORG Sat Dec 18 22:56:18 2004 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 A55CC16A4CE for ; Sat, 18 Dec 2004 22:56:18 +0000 (GMT) Received: from bobball.uchicago.edu (bobball.uchicago.edu [128.135.57.200]) by mx1.FreeBSD.org (Postfix) with SMTP id 48BAB43D45 for ; Sat, 18 Dec 2004 22:56:18 +0000 (GMT) (envelope-from wbwither@bobball.uchicago.edu) Received: (qmail 10923 invoked by uid 1017); 18 Dec 2004 23:31:56 -0000 From: wbwither@bobball.uchicago.edu Date: Sat, 18 Dec 2004 17:31:56 -0600 To: freebsd-questions@freebsd.org Message-ID: <20041218233156.GA10895@bobball.uchicago.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.28i Subject: Identical hard drives, different disklabel sectors/cylinders X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Dec 2004 22:56:18 -0000 Hi all, I've got a problem question about my hard drives. I've installed two brand-new Western Digital 250GB drives on the same channel of a Maxtor-branded PCI/IDE controller (Promise chipset). I've tried different channels, different cables, and using the motherboard's IDE controller -- same thing every time. Here's from /var/log/messages: Dec 18 15:59:23 /kernel: ad4: 238475MB [484521/16/63] at ata2-master UDMA100 Dec 18 15:59:23 /kernel: ad5: 238475MB [484521/16/63] at ata2-slave UDMA100 So you can see it's identifying them the same at startup. Now: su-2.05b# disklabel ad4 # /dev/ad4c: type: unknown disk: amnesiac label: flags: bytes/sector: 512 sectors/track: 63 tracks/cylinder: 255 sectors/cylinder: 16065 cylinders: 30400 sectors/unit: 488392002 rpm: 3600 interleave: 1 trackskew: 0 cylinderskew: 0 headswitch: 0 # milliseconds track-to-track seek: 0 # milliseconds drivedata: 0 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 488392002 0 unused 0 0 # (Cyl. 0 - 30400*) e: 488392002 0 vinum # (Cyl. 0 - 30400*) su-2.05b# disklabel ad5 # /dev/ad5c: type: unknown disk: amnesiac label: flags: bytes/sector: 512 sectors/track: 63 tracks/cylinder: 16 sectors/cylinder: 1008 cylinders: 484520 sectors/unit: 488397105 rpm: 3600 interleave: 1 trackskew: 0 cylinderskew: 0 headswitch: 0 # milliseconds track-to-track seek: 0 # milliseconds drivedata: 0 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 488397105 0 unused 0 0 # (Cyl. 0 - 484520*) e: 488397105 0 vinum # (Cyl. 0 - 484520*) So you can see, the "sectors/cylinder", "cylinders", and "sectors/unit" are all different, and this results in slightly different final sizes. I've set up vinum to create a mirror using the smaller of the two sizes, and it seems to be working fine, but I'm still worried about the implications of this. Could this mean that one of my hard drives is failing? (Again, they're both brand new.) I tried "disklabel -R"'ing each drive to look like the other one (booting in single-user mode), but it wouldn't let me. So I'm smack out of ideas. I'd appreciate any info or suggestions. Thanks, -Brock Witherspoon