Your array had 5 disks, not counting any spares. You need to start the array with at least 4 of the five disks, spares don't help when starting an array. I don't know why it thinks your disk (hdi1) is a spare. But, that may explain how it was removed from the array. Unless Neil has some magic incantations, I think you are out of luck. If Neil has no ideas, you could try to start the array with the drive that failed (hdk1), but that will cause corruption of any stripes that have changed since the drive was removed from the array. So, save this option as a last resort. Of course, if hdk1 has failed hard, you will not be able to use it. Last resort!!! Corruption will occur! mdadm --assemble --force /dev/md0 /dev/hde1 /dev/hdk1 /dev/hdm1 /dev/hdo1 Guy -----Original Message----- From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of Robert Osiel Sent: Saturday, November 13, 2004 7:36 PM To: linux-raid@xxxxxxxxxxxxxxx Subject: Re: A few mdadm questions 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: <none> > 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@xxxxxxxxxxxxxxxx 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 > > - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
