From owner-freebsd-questions@FreeBSD.ORG Tue Jul 16 23:08:44 2013 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 78E61438 for ; Tue, 16 Jul 2013 23:08:44 +0000 (UTC) (envelope-from nvass@gmx.com) Received: from mout.gmx.net (mout.gmx.net [74.208.4.201]) by mx1.freebsd.org (Postfix) with ESMTP id 2CE747FF for ; Tue, 16 Jul 2013 23:08:44 +0000 (UTC) Received: from moby.local ([77.49.59.95]) by mail.gmx.com (mrgmxus002) with ESMTPSA (Nemesis) id 0M7YR7-1UBmy90szv-00xL31; Wed, 17 Jul 2013 01:08:32 +0200 Message-ID: <51E5D256.5070507@gmx.com> Date: Wed, 17 Jul 2013 02:08:06 +0300 From: Nikos Vassiliadis User-Agent: Mozilla/5.0 (X11; FreeBSD i386; rv:17.0) Gecko/20130714 Thunderbird/17.0.7 MIME-Version: 1.0 To: Johan Hendriks Subject: Re: to gmirror or to ZFS References: <4DFBC539-3CCC-4B9B-AB62-7BB846F18530@gmail.com> <976836C5-F790-4D55-A80C-5944E8BC2575@gmail.com> <51E51558.50302@ShaneWare.Biz> <51E52190.7020008@fjl.co.uk> <6CE5718E-2646-4D8C-AF98-37384B8851C5@mac.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:L0rwq/EaRdh2Tql04S+MVvTeDuuS9AFFTetv0YYEqmz1d5eCgyh d013WeDH3HtELBWqLnfDf1lybJIfl8CXYNmuxNlfdvF9ecNay3EEPU0uMr2GOur8Dl6br0e r38PiznT4zlqVb2lQJRE+IPy98iMdA8OC34v79RSlV81s7UlbbMy6z3VLaDdsZoawFyRrZA p2CAjzcsIXu18fqKorlCw== Cc: freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Jul 2013 23:08:44 -0000 On 07/16/13 21:27, Johan Hendriks wrote: > Op dinsdag 16 juli 2013 schreef Charles Swiger (cswiger@mac.com) het > volgende: > >> Hi-- >> >> On Jul 16, 2013, at 10:33 AM, Johan Hendriks > >> wrote: >> [ ... ] >>> I would us a zfs for the os. >>> I have a couple of servers that did not survive a power failure with >>> gmirror. >>> The problems i had was when the power failed one disk was in a rebuilding >>> state and then when the background fsck started or was busy for some time >>> it would crash the whole server. >> >> Well, "don't do that". :-) > > > When the server reboots because of a powerfailure at night, then it boots. > Then it starts to rebuild the mirror on its own, and later the fsck kicks > in. > > Not much i can do about it. You could add geom_journal which will minimize the time of fsck to a second or something like that. Then you don't have to use background fsck anymore. Actually geom_journal's manual page mentions an interesting side-effect of geom_journal over a geom_mirror: you can turn off component synchronization. Geom_journal will re-play last writes so whatever was changed just before the crash will be re-written to both disks. I haven't used this but it makes sense in theory. > Maybe i should have done it without the automatic attachment for a new > device. I always turn off automatic synchronization or stale components as well. It seems to me that people don't really use geom_journal or maybe they just don't talk about it like it's some sort of secret:) just my two cents, Nikos