From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Osiel Subject: Re: A few mdadm questions Date: Sat, 13 Nov 2004 18:35:39 -0600 Message-ID: <4196A85B.5060106@osiel.org> References: <419580D8.1020900@osiel.org> <200411130421.iAD4LwN03759@www.watkins-home.com> <16789.47235.818038.175157@cse.unsw.edu.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <16789.47235.818038.175157@cse.unsw.edu.au> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Guy/Neil: Thanks a lot for the help. Sorry that I didn't include all of the info in my last message, but this box is off the network right now and doesn't even have a floppy or monitor, so I had to do a little work to get the info out. I tried to start the array with the 3 good disks and the 1 spare, but I got an error to the effect that 3 good + 1 spare drives are not enough to start the array (see below) > cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid5] [multipath] read_ahead not set unused devices: > mdadm -D /dev/md0 mdadm: md device /dev/md0 does not appear to be active > mdadm --assemble --force /dev/md0 /dev/hde1 /dev/hdi1 /dev/hdm1 /dev/hdo1 mdadm: /dev/md0 assembled from 3 drives and 1 spare - not enough to start the array > cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid5] [multipath] read_ahead not set md0: inactive ide/host2/bus0/target0/lun0/part1[0] ide/host4/bus0/target0/lun0/part1[5] ide/host6/bus1/target0/lun0/part1[4] ide/host6/bus0/target0/lun0/part1[3] Some notes: hdk1 is the disk which failed initially hdi1 is the disk which I removed and which thinks it is a 'spare' The other three drives report basically identical info, like this: > mdadm -E /dev/hde1 Magic : a92b4efc Version : 00.90.00 UUID : ec2e64a8:fffd3e41:ffee5518:2f3e858c Creation Time : Sun Oct 5 01:25:49 2003 Build Level: raid5 Device Size : 160079488 (152.66 GiB 163.92 GB) Raid Devices : 5 Total Devices : 5 Preferred Minor : 0 Update Time Sat Sep 25 22:07:26 2004 State : dirty Active Devices : 3 Working Devices : 4 Failed Devices : 1 Spare Devices : 1 Checksum : 4ee5cc77 - correct Events : 0.10 Layout : left-symmetric Chunk Size : 128K Number Major Minor RaidDevice State this 0 22 1 0 active sync 0 0 22 1 0 active sync 1 1 0 0 1 faulty removed 2 2 56 1 2 faulty /dev/ide/host4/bus0/target0/lun0/part1 3 3 57 1 3 active sync /dev/ide/host4/bus1/target0/lun0/part1 4 4 88 1 4 active sync /dev/ide/host6/bus0/target0/lun0/part1 5 5 34 1 5 spare Here are the two drives in question: __________mdadm -E /dev/hdi1: Magic : a92b4efc Version : 00.90.00 UUID : ec2e64a8:fffd3e41:ffee5518:2f3e858c Creation Time : Sun Oct 5 01:25:49 2003 Build Level: raid5 Device Size : 160079488 (152.66 GiB 163.92 GB) Raid Devices : 5 Total Devices : 5 Preferred Minor : 0 Update Time Sat Sep 25 22:07:26 2004 State : dirty Active Devices : 3 Working Devices : 4 Failed Devices : 1 Spare Devices : 1 Checksum : 4ee5cc77 - correct Events : 0.10 Layout : left-symmetric Chunk Size : 128K Number Major Minor RaidDevice State this 5 34 1 5 spare 0 0 22 1 0 active sync 1 1 0 0 1 faulty removed 2 2 56 1 2 faulty /dev/ide/host4/bus0/target0/lun0/part1 3 3 57 1 3 active sync /dev/ide/host4/bus1/target0/lun0/part1 4 4 88 1 4 active sync /dev/ide/host6/bus0/target0/lun0/part1 5 5 34 1 5 spare __________mdadm -E /dev/hdk1 Magic : a92b4efc Version : 00.90.00 UUID : ec2e64a8:fffd3e41:ffee5518:2f3e858c Creation Time : Sun Oct 5 01:25:49 2003 Build Level: raid5 Device Size : 160079488 (152.66 GiB 163.92 GB) Raid Devices : 5 Total Devices : 5 Preferred Minor : 0 Update Time Sat Sep 25 22:07:24 2004 State : dirty Active Devices : 4 Working Devices : 5 Failed Devices : 0 Spare Devices : 1 Checksum : 4ee5cc77 - correct Events : 0.9 Layout : left-symmetric Chunk Size : 128K Number Major Minor RaidDevice State this 2 56 1 2 active sync /dev/ide/host4/bus0/target0/lun0/part1 0 0 22 1 0 active sync 1 1 0 0 1 faulty removed 2 2 56 1 2 active sync /dev/ide/host4/bus0/target0/lun0/part1 3 3 57 1 3 active sync /dev/ide/host4/bus1/target0/lun0/part1 4 4 88 1 4 active sync /dev/ide/host6/bus0/target0/lun0/part1 5 5 34 1 5 spare Neil Brown wrote: >On Friday November 12, bugzilla@watkins-home.com wrote: > > >>First, stop using the old raid tools. Use mdadm only! mdadm would not have >>allowed your error to occur. >> >> > >I'm afraid this isn't correct, though the rest of Guy's advice is very >good (thanks Guy!). > > mdadm --remove >does exactly the same thing as > raidhotremove > >It is the kernel that should (and does) stop you from hot-removing a >device that is working and active. So I'm not quite sure what >happened to Robert... > >Robert: it is always useful to provide specific with the output of > cat /proc/mdstat >and > mdadm -D /dev/mdX > >This avoids possible confusion over terminology. > >NeilBrown > >