From owner-freebsd-questions@FreeBSD.ORG Fri Jan 28 17:08:51 2005 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 673B416A4CE for ; Fri, 28 Jan 2005 17:08:51 +0000 (GMT) Received: from mp.cs.niu.edu (mp.cs.niu.edu [131.156.68.41]) by mx1.FreeBSD.org (Postfix) with ESMTP id 03A2943D46 for ; Fri, 28 Jan 2005 17:08:51 +0000 (GMT) (envelope-from bennett@cs.niu.edu) Received: from mp.cs.niu.edu (bennett@localhost [127.0.0.1]) by mp.cs.niu.edu (8.13.3/8.13.3/d) with ESMTP id j0SH88wL007312; Fri, 28 Jan 2005 11:08:08 -0600 (CST) Date: Fri, 28 Jan 2005 11:08:08 -0600 (CST) From: Scott Bennett Message-Id: <200501281708.j0SH88Aq007311@mp.cs.niu.edu> To: jerrymc@clunix.cl.msu.edu, lorenl@alzatex.com cc: freebsd-questions@freebsd.org Subject: Re: How does FreeBSD access NetBSD, OpenBSD? 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: Fri, 28 Jan 2005 17:08:51 -0000 On Fri, 28 Jan 2005 11:18:55 -0500 (EST) Jerry McAllister wrote: >> >> I have FreeBSD, OpenBSD, and NetBSD on the same hard drive of my system. >> How can I mount the NetBSD or OpenBSD partitions from FreeBSD? >> >> Slice 1 - Ext3fs for data between linux/bsd >> Slice 2 - OpenBSD slice with 4 ufs partitions and swap (a,b,e,f,g) >> Slice 3 - FreeBSD slice with 4 ufs partitions and swap (a,b,d,e,f) >> Slice 4 - Extended slice composed of: >> Slice 5 - NetBSD slice with 4 ufs partitions and swap (a,b,e,f,g) >> Slice 6 - Unformatted as of yet. > >Hmmm, First thing I see is that only 4 slices are allowed on a drive. Not true. In fact, I have 8 slices on one of my drives. The slice entries in the Master Boot Record, wherein they are known as "primary partition" entries, are four in number, but one of those four can point, instead of to a "partition" (i.e., "slice" in UNIX terms), to a chain of "logical partition" table entries, known collectively as the "extended partition". The FreeBSD kernel appears to have no trouble with this at all. The main limitation w.r.t. FreeBSD is that the slice containing the bootable root file system must be a "primary" rather than a "logical". This limitation probably means that FreeBSD's boot loader isn't smart enough to understand and follow the logical partition/slice chain to locate the file system containing the kernel to be loaded. From what I've read, LINUX's LILO boot loader *can* do this. Perhaps the FreeBSD loader will be made smarter someday, but I'd guess that would be a low- priority item on the developer team's to-do list. Scott Bennett, Comm. ASMELG, CFIAG ********************************************************************** * Internet: bennett at cs.niu.edu * *--------------------------------------------------------------------* * "A well regulated and disciplined militia, is at all times a good * * objection to the introduction of that bane of all free governments * * -- a standing army." * * -- Gov. John Hancock, New York Journal, 28 January 1790 * **********************************************************************