From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1Q3dD1-0005BO-I9 for garchives@archives.gentoo.org; Sat, 26 Mar 2011 23:47:55 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 564F61C064; Sat, 26 Mar 2011 23:46:32 +0000 (UTC) Received: from mail-ww0-f53.google.com (mail-ww0-f53.google.com [74.125.82.53]) by pigeon.gentoo.org (Postfix) with ESMTP id 039281C064 for ; Sat, 26 Mar 2011 23:46:31 +0000 (UTC) Received: by wwj40 with SMTP id 40so2437972wwj.10 for ; Sat, 26 Mar 2011 16:46:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:from:to:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding :content-type; bh=lBLzHkOMaSVRHNcDodr1HtlTEXTGw/gEc5CQIVsf1Gc=; b=Ftik8CiKRy+86pQ4Gap5XCRn8pG1WTXN+tzkboEZLKfOZxliEbkx06m+wA7gkv3XGj HUKXgwTOnOuZCXyryUmrQ0Oig2vNtjTIfRvte/BzA5LITTOJNpZKPoDq8FxR8Jexac6S +Fmg+WRq7Ta8KptLwmmE/HeT9pZ7YOzgdrp2U= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:message-id:user-agent:in-reply-to:references :mime-version:content-transfer-encoding:content-type; b=Aif71stK0bUO4asDBlKFRkPoq0zlsXZgW6Bw7ps5m+WlnWrbUtGYUDv7MtvnfNwaF1 JyAp4JZZYYLYq425f99+9cFf5L1xi1WFHdTofg91GgNfkfpvxquzaD2LJmF9SXZKbRvm 8TFKSgkuIfvtKCl9bjusIHdA7hZ++TuPQM6rI= Received: by 10.227.0.88 with SMTP id 24mr2372905wba.123.1301183191234; Sat, 26 Mar 2011 16:46:31 -0700 (PDT) Received: from nazgul.localnet (196-215-2-50.dynamic.isadsl.co.za [196.215.2.50]) by mx.google.com with ESMTPS id b20sm1200833wbb.67.2011.03.26.16.46.29 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 26 Mar 2011 16:46:30 -0700 (PDT) From: Alan McKinnon To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] LVM (Was: the best filesystem for server: XFS or JFS (or?)) Date: Sun, 27 Mar 2011 01:46:26 +0200 Message-Id: <2613115.sLQyzzM4Gh@nazgul> User-Agent: KMail/4.6 beta4 (Linux/2.6.37-ck; KDE/4.6.1; x86_64; git-721ea32; 2011-03-10) In-Reply-To: References: <4D8E66C0.6080305@gmail.com> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" X-Archives-Salt: X-Archives-Hash: d44939429c8c0e278c1959ee92330bf1 On Saturday 26 March 2011 15:36:19 Mark Knecht wrote: > Dale, > I understand your position and concerns. While I have a number of > systems, I have little time or patience for dealing with a lot of this > stuff and LVM has been one of them. > > One thing I'm considering to try out LVM is a second Gentoo > installation on an already running system. It will either be a 50GB > partition of its own, or a Virtualbox VM. I'd do the normal Gentoo > install for LVM, figure out how it works, etc., and then decide if I > want to use it in the future. Well I can help with that, or at least provide some tips. Delivering Red Hat's training courses exposes you to all the weird and wonderful ways people misunderstand LVM and the even weirder ways gnome tools present the subject... Logically, LVM sits between your physical disks (or raid arrays if you use that) and the filesystem. All it is is a way to manipulate these things called "block devices" in ways that you normally can't do without LVM. Like if you have 4 partitions on a disk and want to make the third one bigger. Using just fdisk, you can't do that without making backups and restoring. Or creating a filesystem larger than any one disk. So LVM takes a bunch of disks or arrays and lets you combine them in ways you want them (not ways the hardware forces you to have them). And that's all it does - forget all the nonsense in the man pages about aligning stripes to make mirrors - that just confuses people and makes them think it's some fancy raid. You could argue that LVM exposes too much complexity by letting you see the physical volumes (pv), volume groups (vg) and logical volumes (lv), and I won't argue with that. It's a trade between flexibility and complexity. I'm happy with it, others might not be. -- alan dot mckinnon at gmail dot com