From owner-freebsd-questions@freebsd.org Thu Feb 21 06:55:30 2019 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id BC62314F9EFB for ; Thu, 21 Feb 2019 06:55:30 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "mout.kundenserver.de", Issuer "TeleSec ServerPass DE-2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id A4415925E3 for ; Thu, 21 Feb 2019 06:55:29 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from r56.edvax.de ([92.193.157.173]) by mrelayeu.kundenserver.de (mreue009 [212.227.15.167]) with ESMTPA (Nemesis) id 1MiagR-1hZ5kI0WTH-00fgh6; Thu, 21 Feb 2019 07:55:17 +0100 Date: Thu, 21 Feb 2019 07:55:15 +0100 From: Polytropon To: "@lbutlr" Cc: freebsd-questions@freebsd.org Subject: Re: Duplicating file system Message-Id: <20190221075515.c815b269.freebsd@edvax.de> In-Reply-To: References: <0A33E3BE-96C9-4D83-B9F7-D4D2792B5161@kreme.com> <32153EA7-4BC5-4EE2-98FA-5BDEE1903BA3@cretaforce.gr> <4CAB4BC4-0473-41CF-AF03-D1CE796F5545@cretaforce.gr> <0F4BBC09-3F9D-4740-A8E4-BB3B87F2A657@kreme.com> <20190221032121.c0006dfe.freebsd@edvax.de> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:Xvka63dokK1Xeu/zodCvB5w10TG3lfa2tJh4ZgA5AqcarEF72n6 J+R2ULYvzniklvI0m98+f8rKNkEtvOnZut4AWF/dGLfbhs86bHIUw4IgdHE96xKbdG7qbjH 8RiJzXzEeIS9AY8Y8usyknT+hKtkzjnHLpWLtB+fZ0cv5URfCa3hqOl36N/F2rROjIDIjuO bqGBZ2PcL8B7k/GWbtnUg== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:dcB8ScrwgfA=:fL8TQVSuuew3uymWPmzgh/ Rx4FHycfDiS/22bpsD+3xrOZRfjDcePufwGV/7p5ZZlPFX84Zcyljuo+4HRLfydDDOmw5D1vb hZH0G0CL1KJFh3o+3FNqmu/WeI/O8sdOBHGHwzaVcWEe9g3O2eRNZeY4H2F9SbiFL95XkLE5D j/h4wf5bbQoHHBeEW98RjjZNkV6UlWWlXbzLoU/daWAF/2+LYHF8ixjWepXCyJShFo647b1VD 72KJSPQgAGUKRqhH1Kc4vO0vDChIttizxEaBGImZYqB0lDepBoef6gO/VxUWhlchVivA/KxiY QiUN0jPt559Vs9MKvK5ES8x48+PCLrInwhqtIf2i/PcZzaAVQ1dbzL9c9WeWDT9naIfMb4fw+ WdPiaq+6ZOID+1dh4xjyea4CLZ1B89KuI9g/vdSthavnmw9AwzSJ3h+erh/KHD/1UxC7AA1HB TuHplkTT0W1EmVxU0CsQaK10PM1TlJ9R+Z1oNDs1hE0wh/M6j+KmolAZhMGKfZV3JaqySLttj 9BSJTPq9MkYYK1ezDSuQJYUjMP9tS06Zz/jqBnXltSlrvZDya3e8aax2OeTMEc64pHtCSoc6y w0tlPtMZnPuLIHiRICR1LJ4itudmiJeAokUyyfW6oZE0eH4yW/l1v+J/Zw/n0nquZXKBvI7t3 9AK0ziqOnpDD/AeWUgjM3INYOsXQ0P2R2aGkBc53mEw6Tpd8URbA6OftUMzwFUKCgjWg4vMLC DAQzZTXHClfEmcDhVLhjsDTP+ClQ6BbKJaQmyBIw726Wr57g7SKhQk3tkLk= X-Rspamd-Queue-Id: A4415925E3 X-Spamd-Bar: ++++++ Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [6.19 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; HAS_REPLYTO(0.00)[freebsd@edvax.de]; TO_DN_SOME(0.00)[]; MV_CASE(0.50)[]; HAS_ORG_HEADER(0.00)[]; MX_GOOD(-0.01)[cached: mx01.schlund.de]; RCPT_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; RCVD_TLS_LAST(0.00)[]; R_DKIM_NA(0.00)[]; ASN(0.00)[asn:8560, ipnet:212.227.0.0/16, country:DE]; MIME_TRACE(0.00)[0:+]; RECEIVED_SPAMHAUS_PBL(0.00)[173.157.193.92.zen.spamhaus.org : 127.0.0.10]; ARC_NA(0.00)[]; REPLYTO_EQ_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; NEURAL_SPAM_SHORT(0.85)[0.852,0]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[edvax.de]; AUTH_NA(1.00)[]; NEURAL_SPAM_MEDIUM(1.00)[1.000,0]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(1.00)[1.000,0]; RCVD_IN_DNSWL_NONE(0.00)[130.126.227.212.list.dnswl.org : 127.0.5.0]; MID_CONTAINS_FROM(1.00)[]; R_SPF_NA(0.00)[]; RWL_MAILSPIKE_POSSIBLE(0.00)[130.126.227.212.rep.mailspike.net : 127.0.0.17]; RCVD_COUNT_TWO(0.00)[2]; IP_SCORE(0.94)[ip: (3.66), ipnet: 212.227.0.0/16(-0.82), asn: 8560(1.89), country: DE(-0.01)] X-Spam: Yes X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Feb 2019 06:55:31 -0000 On Wed, 20 Feb 2019 20:59:21 -0700, @lbutlr wrote: > On 20 Feb 2019, at 19:21, Polytropon wrote: > > With this in mind, I'd start with an 1:1 copy using dd, and from that > > point on, have a scheduled job of rsync or cpdup in place to have any > > source changes affect the "copy drive". > > I will try cpdup as I have tried rsync already and it is too > resource intensive to run it constantly. Even with a 5 minute > delay sometimes a task will not finish before the next one > starts and then a cascade will bring the system down as more > and more processes get stuck. This makes the scenario even more look like a situation where a mirrored approach (like software RAID, gmirror) is a good solution; writes will happen in quasi-parallel and transparent to the writing process, so those race conditions won't appear. But definitely try cpdup, it might work fast enough to fit the time window. :-) -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...