From owner-freebsd-questions Sun May 31 16:54:59 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id QAA17408 for freebsd-questions-outgoing; Sun, 31 May 1998 16:54:59 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from mail-ftp.nordicdms.com ([207.21.168.100]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id QAA17331 for ; Sun, 31 May 1998 16:54:19 -0700 (PDT) (envelope-from walton@nordicdms.com) Received: from mail-ftp (mail.nordicdms.com [207.21.168.101]) by mail-ftp.nordicdms.com (Post.Office MTA v3.1 release PO205e ID# 0-0U10L2S100) with SMTP id AAA277; Sun, 31 May 1998 16:54:17 -0700 From: walton@nordicdms.com (Dave Walton) Organization: Nordic Entertainment Worldwide To: Greg Lehey , freebsd-questions@FreeBSD.ORG Date: Sun, 31 May 1998 16:54:17 -800 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Subject: Re: fdisk slice oddities Reply-to: walton@nordicdms.com In-reply-to: <19980530185741.K20360@freebie.lemis.com> References: <19980530073409264.AAA277@mail.nordicdms.com>; from Dave Walton on Sat, May 30, 1998 at 12:34:09AM +0000 Message-ID: <19980531235417422.AAA277@mail.nordicdms.com> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On 30 May 98 at 18:57, Greg Lehey wrote: > Dedicated mode. It's not only not dangerous, it's safer than > non-dedicated mode. Really? Why is it safer? Sysinstall calls it "dangerously dedicated", BTW. > > Is there some particular reason why dangerously dedicated mode > > changes the drive geometry? > > It might come closer to getting it right. That's just it... It's not changing to a more correct geometry, it's changing to a geometry with < 1024 cylinders. For example, on this 6.5GB drive that I'm working with right now, dmesg and fdisk report the geometry as 13328/15/63. If I use the whole disk in "dedicated mode", the geometry changes to 784/255/63. > I suppose the most important difference is that no modern disks have a > rigid geometry any more (in other words, the terms cylinders, heads > and sectors are all faked). All we care about is the LBA (logical > block addressing) mode. Which is why I'm surprised that fdisk changes to something other than LBA mode for "dedicated mode". > Apart from the observation, did you have any problems? No, it just strikes me as a peculiar behavior, so I thought I'd mention it. By the way, given the choice between an LBA geometry and a <1024 geometry, is there any particular reason to go with one over the other? Thanks, Dave ---------------------------------------------------------------------- Dave Walton Webmaster, Postmaster Nordic Entertainment Worldwide walton@nordicdms.com http://www.nordicdms.com ---------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message