From owner-freebsd-fs@freebsd.org Tue Sep 22 07:37:14 2015 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 15E0EA068A5 for ; Tue, 22 Sep 2015 07:37:14 +0000 (UTC) (envelope-from jg@internetx.com) Received: from mx1.internetx.com (mx1.internetx.com [62.116.129.39]) by mx1.freebsd.org (Postfix) with ESMTP id CBDE21CCD for ; Tue, 22 Sep 2015 07:37:13 +0000 (UTC) (envelope-from jg@internetx.com) Received: from localhost (localhost [127.0.0.1]) by mx1.internetx.com (Postfix) with ESMTP id BBA341472004 for ; Tue, 22 Sep 2015 09:27:07 +0200 (CEST) X-Virus-Scanned: InterNetX GmbH amavisd-new at ix-mailer.internetx.de Received: from mx1.internetx.com ([62.116.129.39]) by localhost (ix-mailer.internetx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id NbyCFpadUjWz for ; Tue, 22 Sep 2015 09:27:05 +0200 (CEST) Received: from [192.168.100.26] (pizza.internetx.de [62.116.129.3]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mx1.internetx.com (Postfix) with ESMTPSA id 3E694147200C for ; Tue, 22 Sep 2015 09:27:04 +0200 (CEST) Subject: Re: [HAST] ZFS, many disks, write order References: To: freebsd-fs@freebsd.org Reply-To: jg@internetx.com From: InterNetX - Juergen Gotteswinter Message-ID: <560102BD.6040703@internetx.com> Date: Tue, 22 Sep 2015 09:26:53 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Sep 2015 07:37:14 -0000 One of the great Hast Features is that it Hides Disk Failures from ZFS, this has been already discussed on this List a few Months ago. Single ZIL Flash Drive is also not such a great Idea. I whould suggest to start from scratch with "ZFS Best Practices". Am 21.09.2015 um 23:10 schrieb Ben RUBSON: > Hello, > > I plan to use HAST to synchronize a ZFS pool between 2 servers. > The ZFS pool has 3 RAID-Z2 VDEVs (8+2), + 3 spares. > +1 mirror for SLOG. > +1 mirror for L2ARC. > So a total of 37 disks (4TB each). > 40Gb/s network bandwidth between the 2 servers. > > Will I have to define each of the 37 disks/resources in hast.conf ? > Stupid question, but will this setup (with so many resources) work ? > > Will write IOs be ordered on the secondary node in the same order (over all the 37 devices) as they occurred on the primary node ? > This of course to have the secondary node consistent, even after a power failure of the primary during a high IO load, leading into an import -F on the secondary node. > > In HAST, each resource seems to be "independent" from the others. > In DRBD, as an example, we can put several volumes in a same resource to guarantee write order over all the volumes (disks) of the resource. > Example : > > resource r0 { > volume 0 { > device /dev/drbd0; > disk /dev/c0v0; > } > volume 1 { > device /dev/drbd1; > disk /dev/c0v1; > } > } > > What about HAST then ? > Of course I would have liked to have my 37 disks as volumes in the same resource, as in the example above. > > Thank you very much for your help ! > > Best regards, > > Ben > > _______________________________________________ > freebsd-fs@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-fs > To unsubscribe, send any mail to "freebsd-fs-unsubscribe@freebsd.org" >