From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Carl-=?ISO-8859-1?Q?Johan_W=E4gner?=" Subject: Re: RAID 5 with bad blocks Date: Mon, 27 Sep 2010 17:43:23 +0200 Message-ID: <20100926232102.M67000@agusta.se> References: <20100925000351.M29572@agusta.se> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Return-path: In-Reply-To: <20100925000351.M29572@agusta.se> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org Cc: fafler@gmail.com List-Id: linux-raid.ids A follow up on my suggestion: > Would it be possible to copy (with 'dd') the device (/dev/sdb) with sector > errors to a fourth disk (/dev/sde) and then remove the faulty sdb- > drive and reposition the newly copied sde to sdb's position to have > this act as the first sdb-drive, now working without any physical > faults, even if the data is incomplete in sectors; and now being > possible to recover the third drive (/dev/sdd1)? 'dd' is NOT the program one would want to use for this task. "ddrescue" is the one! NB: dd_rescue is not the same program, and may or may not work. Just note that "apt-get install ddrescue" installs dd_rescue, not ddrescue... ddrescue is downloaded (with e g curl) from: # curl ftp.gnu.org/gnu/ddrescue/ddrescue-1.13.tar.gz >ddrescue-1.13.tar.gz Having installed, copied disk to disk and swapped disks the RAID started ti rebuild /dev/sdd1 and I have now a clean array again!