From owner-freebsd-questions@FreeBSD.ORG Sat Aug 7 12:00:24 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 754BA16A4CE for ; Sat, 7 Aug 2004 12:00:24 +0000 (GMT) Received: from smtp.infracaninophile.co.uk (ns0.infracaninophile.co.uk [81.2.69.218]) by mx1.FreeBSD.org (Postfix) with ESMTP id AF7A443D2D for ; Sat, 7 Aug 2004 12:00:22 +0000 (GMT) (envelope-from m.seaman@infracaninophile.co.uk) Received: from happy-idiot-talk.infracaninophile.co.uk (localhost [IPv6:::1]) i77C0HYF016107 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 7 Aug 2004 13:00:17 +0100 (BST) (envelope-from matthew@happy-idiot-talk.infracaninophile.co.uk) Received: (from matthew@localhost)id i77C0H0K016106; Sat, 7 Aug 2004 13:00:17 +0100 (BST) (envelope-from matthew) Date: Sat, 7 Aug 2004 13:00:17 +0100 From: Matthew Seaman To: Odhiambo Washington , freebsd-questions@freebsd.org Message-ID: <20040807120017.GA96092@happy-idiot-talk.infracaninophile.co.uk> Mail-Followup-To: Matthew Seaman , Odhiambo Washington , freebsd-questions@freebsd.org References: <20040807103639.GB1807@ns2.wananchi.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2oS5YaxWCcQjTEyO" Content-Disposition: inline In-Reply-To: <20040807103639.GB1807@ns2.wananchi.com> User-Agent: Mutt/1.5.6i X-Greylist: Message not sent from an IPv4 address, not delayed by milter-greylist-1.5.3 (smtp.infracaninophile.co.uk [0.0.0.0]); Sat, 07 Aug 2004 13:00:17 +0100 (BST) X-Virus-Scanned: clamd / ClamAV version devel-20040705, clamav-milter version 0.74a on smtp.infracaninophile.co.uk X-Virus-Status: Clean X-Spam-Status: No, hits=-4.8 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=2.64 X-Spam-Checker-Version: SpamAssassin 2.64 (2004-01-11) on happy-idiot-talk.infracaninophile.co.uk Subject: Re: Mounting two different disk slices on the same mount point 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, 07 Aug 2004 12:00:24 -0000 --2oS5YaxWCcQjTEyO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Aug 07, 2004 at 01:36:39PM +0300, Odhiambo Washington wrote: >=20 > Hello FreeBSD gurus, >=20 > Some linux guy gave me a strange idea: >=20 > You have two disks, /dev/da1s1e and /dev/da2s1e and I mount the > two to a single mount point. > Do I end up with the total capacity of the two disks on the said > mount point? > To be a bit clear, da1 is, say, 36GB and da2 is 72GB and I mount > as above to /mnt > Does /mnt now have 108GB? > What are the dangers of doing this? > How does the system use the disks? >=20 > I haven't tested this anyway. >=20 >=20 > Is this something sane? >=20 >=20 > Clues will be highly appreciated. That sounds a bit muddled. If you try mounting two partitions literally in the same place, either one will overlay the other so you can only access the last mounted partition, or you'll get an error message and fail to mount the second one. (Which occurs depends on the filesystem type). What I think your Linux using friends were thinking of, even if they were unclear on the concept, is some form of logical volume management. Under FreeBSD, you could use vinum(8) to create a concat volume from the two partitions, which would give you give you a filesystem the size of the sum of both components. That's not new functionality. It's been available in FreeBSD for ages (since 2.x I believe) through vinum(8) or one of it's predecessors like ccd(4). Cheers, Matthew --=20 Dr Matthew J Seaman MA, D.Phil. 26 The Paddocks Savill Way PGP: http://www.infracaninophile.co.uk/pgpkey Marlow Tel: +44 1628 476614 Bucks., SL7 1TH UK --2oS5YaxWCcQjTEyO Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (FreeBSD) iD8DBQFBFMRRiD657aJF7eIRAsdnAJ9TtUG4v7cdh1qaqco+qbGVuDAJKACfTj24 b+xeq4YE7HlvXYbQpHD0cHA= =C/rJ -----END PGP SIGNATURE----- --2oS5YaxWCcQjTEyO--