From owner-freebsd-fs@freebsd.org Tue May 31 15:41:44 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 14C41B55C37 for ; Tue, 31 May 2016 15:41:44 +0000 (UTC) (envelope-from feld@FreeBSD.org) Received: from out2-smtp.messagingengine.com (out2-smtp.messagingengine.com [66.111.4.26]) (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 E32281AAD for ; Tue, 31 May 2016 15:41:43 +0000 (UTC) (envelope-from feld@FreeBSD.org) Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 91F2C256A7; Tue, 31 May 2016 11:41:42 -0400 (EDT) Received: from web4 ([10.202.2.214]) by compute4.internal (MEProxy); Tue, 31 May 2016 11:41:42 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-sasl-enc:x-sasl-enc; s=smtpout; bh=5l6JVvDnNugP07a DBhdynSMZPwQ=; b=PgHj+EQm9AUpPQr0CzIE1RFRDvngzgRnsh0cDkedMlCk4M5 PKuaWgqe82EWoKcpnUBusLxbFPjA7arK5yeusooJ/7t2dVp/G3Dj3JQQ+61w93/o OPuGOgDfjksefaXl8lKzpt3Ciuyy/U2rcenJqUSge1EkGP/8UXlmFQnwOAuk= Received: by mailuser.nyi.internal (Postfix, from userid 99) id 561CBCC350; Tue, 31 May 2016 11:41:42 -0400 (EDT) Message-Id: <1464709302.3816627.623738921.185742BF@webmail.messagingengine.com> X-Sasl-Enc: wXjCaEqR6wcZ8pfiYSsLTctjux4spfiWt6++LfhuAtL8 1464709302 From: Mark Felder To: Willem Jan Withagen , "Kevin P. Neal" , Evgeny Sam Cc: freebsd-fs@freebsd.org MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain X-Mailer: MessagingEngine.com Webmail Interface - ajax-e26fc460 In-Reply-To: References: <20160530202147.GA40137@neutralgood.org> Subject: Re: ZFS - RAIDZ1 Recovery (Evgeny Sam) Date: Tue, 31 May 2016 10:41:42 -0500 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: Tue, 31 May 2016 15:41:44 -0000 On Tue, May 31, 2016, at 05:15, Willem Jan Withagen wrote: > On 30-5-2016 22:21, Kevin P. Neal wrote: > > There are several good ways to duplicate a disk, and at the top of the > > list are tools known to the people you are going to need help from. That > > means using the 'dd' command to duplicate the entire disk including the > > GPT labels. Or use something from Polytropon's list posted to these lists > > (usually the questions list mostly) every so often. > > > > The dd command when given the "conv=noerror,sync" option can be used to > > duplicate an entire disk. Then a ZFS scrub can correct the lost blocks. > > Might I suggest dd_rescue here? > > Sort of designed for precisely this problem. > Does large bulk transfers, but when in error it reduces blocksize to the > sector, and tries several times.... > And there are lots of other options. > > So it is fast and as accurate as it can get. > > Save my life a few times. > FreeBSD has its own built-in dd_rescue alternative called recoverdisk -- Mark Felder ports-secteam member feld@FreeBSD.org