From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roberto Nunnari Subject: failed drive in raid 1 array Date: Wed, 23 Feb 2011 17:52:39 +0100 Message-ID: <4D653B57.1030203@supsi.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello. I have a linux box, with two 2TB sata HD in raid 1. Now, one disk is in failed state and it has no spares: # cat /proc/mdstat Personalities : [raid1] md1 : active raid1 sdb4[2](F) sda4[0] 1910200704 blocks [2/1] [U_] md0 : active raid1 sdb1[1] sda2[0] 40957568 blocks [2/2] [UU] unused devices: The drives are not hot-plug, so I need to shutdown the box. My plan is to: # sfdisk -d /dev/sdb > sdb.sfdisk # mdadm /dev/md1 -r /dev/sdb4 # mdadm /dev/md0 -r /dev/sdb1 # shutdown -h now replace the disk and boot (it should come back up, even without one drive, right?) # sfdisk /dev/sdb < sdb.sfdisk # mdadm /dev/md1 -a /dev/sdb4 # mdadm /dev/md0 -a /dev/sdb1 and the drives should start to resync, right? This is my first time I do such a thing, so please, correct me if the above is not correct, or is not a best practice for my configuration. My last backup of md1 is of mid november, so I need to be pretty sure I will not lose my data (over 1TB). A bit abount my environment: # mdadm --version mdadm - v1.12.0 - 14 June 2005 # cat /etc/redhat-release CentOS release 4.8 (Final) # uname -rms Linux 2.6.9-89.31.1.ELsmp i686 Thank you very much and best regards. Robi