From owner-freebsd-fs@freebsd.org Thu Aug 11 09:33:15 2016 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 15FC9BB5202 for ; Thu, 11 Aug 2016 09:33:15 +0000 (UTC) (envelope-from borjam@sarenet.es) Received: from cu1176c.smtpx.saremail.com (cu1176c.smtpx.saremail.com [195.16.148.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id CC7271575 for ; Thu, 11 Aug 2016 09:33:14 +0000 (UTC) (envelope-from borjam@sarenet.es) Received: from [172.16.8.36] (izaro.sarenet.es [192.148.167.11]) by proxypop02.sare.net (Postfix) with ESMTPSA id 141BC9DC5CE; Thu, 11 Aug 2016 11:24:41 +0200 (CEST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: HAST + ZFS + NFS + CARP From: Borja Marcos In-Reply-To: <20160811091016.GI70364@mordor.lan> Date: Thu, 11 Aug 2016 11:24:40 +0200 Cc: Jordan Hubbard , freebsd-fs@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: <1AA52221-9B04-4CF6-97A3-D2C2B330B7F9@sarenet.es> References: <6035AB85-8E62-4F0A-9FA8-125B31A7A387@gmail.com> <20160703192945.GE41276@mordor.lan> <20160703214723.GF41276@mordor.lan> <65906F84-CFFC-40E9-8236-56AFB6BE2DE1@ixsystems.com> <61283600-A41A-4A8A-92F9-7FAFF54DD175@ixsystems.com> <20160704183643.GI41276@mordor.lan> <20160704193131.GJ41276@mordor.lan> <20160811091016.GI70364@mordor.lan> To: Julien Cigar X-Mailer: Apple Mail (2.3124) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Aug 2016 09:33:15 -0000 > On 11 Aug 2016, at 11:10, Julien Cigar wrote: >=20 > As I said in a previous post I tested the zfs send/receive approach = (with > zrep) and it works (more or less) perfectly.. so I concur in all what = you > said, especially about off-site replicate and synchronous replication. >=20 > Out of curiosity I'm also testing a ZFS + iSCSI + CARP at the moment,=20= > I'm in the early tests, haven't done any heavy writes yet, but ATM it=20= > works as expected, I havent' managed to corrupt the zpool. I must be too old school, but I don=E2=80=99t quite like the idea of = using an essentially unreliable transport (Ethernet) for low-level filesystem operations. In case something went wrong, that approach could risk corrupting a = pool. Although, frankly, ZFS is extremely resilient. One of mine even survived a SAS HBA problem = that caused some silent corruption. The advantage of ZFS send/receive of datasets is, however, that you can = consider it essentially atomic. A transport corruption should not cause trouble = (apart from a failed "zfs receive") and with snapshot retention you can even roll back. You = can=E2=80=99t roll back zpool replications :) ZFS receive does a lot of sanity checks as well. As long as your zfs = receive doesn=E2=80=99t involve a rollback to the latest snapshot, it won=E2=80=99t destroy anything by mistake. = Just make sure that your replica datasets aren=E2=80=99t mounted and zfs receive won=E2=80=99t complain. Cheers, Borja.