From owner-freebsd-hackers@FreeBSD.ORG Sun Oct 12 01:31:03 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B48FD106568B for ; Sun, 12 Oct 2008 01:31:03 +0000 (UTC) (envelope-from mwm-keyword-freebsdhackers2.e313df@mired.org) Received: from mired.org (five.mired.org [66.92.153.75]) by mx1.freebsd.org (Postfix) with ESMTP id 579388FC08 for ; Sun, 12 Oct 2008 01:31:03 +0000 (UTC) (envelope-from mwm-keyword-freebsdhackers2.e313df@mired.org) Received: (qmail 93918 invoked by uid 1001); 11 Oct 2008 21:28:31 -0400 Received: from bhuda.mired.org (bhuda [192.168.195.1]) by bhuda (tmda-ofmipd) with ESMTP; Sat, 11 Oct 2008 21:28:30 -0400 Date: Sat, 11 Oct 2008 21:28:29 -0400 To: Jeremy Chadwick Message-ID: <20081011212829.57b889d7@bhuda.mired.org> In-Reply-To: <20081011112431.GA60924@icarus.home.lan> References: <20081010023428.87556dt18ejyzf48@mail.ispro.net> <20081009200641.60d0b236@bhuda.mired.org> <48EF5052.2000707@ispro.net> <20081010144111.GA34609@icarus.home.lan> <20081010112952.52b8209b@bhuda.mired.org> <20081010154249.GA35859@icarus.home.lan> <20081010122228.355c2c3e@bhuda.mired.org> <20081011104409.GA58698@icarus.home.lan> <20081011112431.GA60924@icarus.home.lan> Organization: Meyer Consulting X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.11; amd64-portbld-freebsd7.0) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Delivery-Agent: TMDA/1.1.12 (Macallan) From: Mike Meyer Cc: freebsd-hackers@freebsd.org, Mike Meyer Subject: Re: continuous backup solution for FreeBSD X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 12 Oct 2008 01:31:03 -0000 On Sat, 11 Oct 2008 04:24:31 -0700 Jeremy Chadwick wrote: > > I'm asking, because I want to deploy some zfs fileservers soon, and so > > far the solution is either PXE boot, or keep one disk UFS (or boot off a USB) > > Today's /(root+usr) is somewhere between .5 to 1Gb(kernel+debug+src), > > and is readonly, so having 1 disk UFS seems to be a pitty. > > Hold on a minute. "One disk" has nothing to do with the filesystem. > You asked if FreeBSD could boot off of a specific filesystem, and I > answered that -- I didn't state anything about disk counts. Now you're > changing the focus. :-) > > I'm pretty sure FreeBSD can boot off of gmirror setups (see above, > boot2/loader should work off of gmirror), which means >1 disk. You > do not have to gmirror the entire disk, you can gmirror just a slice > (AFAIK). > > I think (hope?) you can use the "remaining" (e.g. non-UFS/non-gmirror) > part of the 2nd disk for ZFS as well, otherwise the space would go > to waste. The "Root on ZFS configuration" FreeBSD ZFS Wiki page > seems to imply you can. You mean like this: bhuda% gmirror status Name Status Components mirror/boot COMPLETE ad0s1a ad1s1a bhuda% zpool status pool: internal state: ONLINE scrub: none requested config: NAME STATE READ WRITE CKSUM internal ONLINE 0 0 0 mirror ONLINE 0 0 0 ad0s1d ONLINE 0 0 0 ad1s1d ONLINE 0 0 0 errors: No known data errors Yes, I don't get the benefits of having /boot on a zfs partition, but I do get the benefits of having it on a mirror: automatic duplication, reads from either device, and I can use either device stand-alone if I break the mirror. Note that FreeBSD booting from a gmirror'ed partition/disk can't boot from the gmirror device - boot doesn't understand gmirror. It can, however, boot from any of the devices participating in the mirror. The mirror device appears after the kernel is loaded. Given that I have to have a separate boot partition, having swap partitions on the drives is a win compared to swapping to a zvol. I'm going to investigate putting /boot on an SSD of some kind so that ZFS can have the entire disk. http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org