From owner-freebsd-questions@freebsd.org Mon Jan 30 15:28:51 2017 Return-Path: Delivered-To: freebsd-questions@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 E8666CC7CCD for ; Mon, 30 Jan 2017 15:28:51 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from wonkity.com (wonkity.com [67.158.26.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "wonkity.com", Issuer "wonkity.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id B0EDFF0F for ; Mon, 30 Jan 2017 15:28:51 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from wonkity.com (localhost [127.0.0.1]) by wonkity.com (8.15.2/8.15.2) with ESMTPS id v0UFSo96089812 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 30 Jan 2017 08:28:50 -0700 (MST) (envelope-from wblock@wonkity.com) Received: from localhost (wblock@localhost) by wonkity.com (8.15.2/8.15.2/Submit) with ESMTP id v0UFSo7Y089809; Mon, 30 Jan 2017 08:28:50 -0700 (MST) (envelope-from wblock@wonkity.com) Date: Mon, 30 Jan 2017 08:28:50 -0700 (MST) From: Warren Block To: David Christensen cc: freebsd-questions@freebsd.org Subject: Re: FreeBSD 11.0-RELEASE-p7 i386 system drive imaging and migration In-Reply-To: Message-ID: References: <86bmupg0gi.fsf@WorkBox.homestead.org> <2973d1ea-202f-60fa-2930-eec05b626cfb@holgerdanske.com> User-Agent: Alpine 2.20 (BSF 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (wonkity.com [127.0.0.1]); Mon, 30 Jan 2017 08:28:50 -0700 (MST) X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 30 Jan 2017 15:28:52 -0000 On Sun, 29 Jan 2017, David Christensen wrote: >> Writing SSDs with dd is not good, limiting their wear leveling. > > That's why I used zcat rather than dd for writing to the cloned SSD. If/when > I know enough to use zfs send/ receive, that will be best. zcat is no different than dd in this case. When you write a binary image, the SSD can't tell which blocks are truly in use, because they have all been written.