A linux utility used to manage software RAID devices.
Questions tagged [mdadm]
821 questions
53
votes
9 answers
How to interrupt software raid resync?
I want to interrupt a running resync operation on a debian squeeze software raid. (This is the regular scheduled compare resync. The raid array is still clean in such a case. Do not confuse this with a rebuild after a disk failed and was…
Adam5
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38
votes
5 answers
Recover RAID 5 data after created new array instead of re-using
Folks please help - I am a newb with a major headache at hand (perfect storm situation).
I have a 3 1tb hdd on my ubuntu 11.04 configured as software raid 5. The data had been copied weekly onto another separate off the computer hard drive until…
Brigadieren
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34
votes
7 answers
How beneficial are self-healing filesystems for general usage?
I have recently looked into advanced filesystems (Btrfs, ZFS) for data redundancy and availability and got interested in the additional functionality they provide, especially their "self-healing" capabilities against data corruption.
However, I…
Prototype700
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25
votes
5 answers
Best way to grow Linux software RAID 1 to RAID 10
mdadm does not seem to support growing an array from level 1 to level 10.
I have two disks in RAID 1. I want to add two new disks and convert the array to a four disk RAID 10 array.
My current strategy:
Make good backup.
Create a degraded 4 disk…
Hans Malherbe
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25
votes
4 answers
How do I move a Linux software RAID to a new machine?
I have a newly built machine with a fresh Gentoo Linux install and a software RAID 5 array from another machine (4 IDE disks connected to off-board PCI controllers). I've successfully moved the controllers to the new machine; the drives are detected…
romandas
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21
votes
4 answers
Can you change the metadata version on an existing array?
So grub requires metadata version 0.90 I'm wondering if I can change my existing arrays to use that instead of the default which is 1.2. That way I don't have to go about a reinstall. If yes, how can I do it?
xenoterracide
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17
votes
3 answers
How to re-add a drive when RAID is in degraded mode?
I am running an unmanaged Ubuntu server and due to recent performance issue and sent a request to the provider only to receive the following response:
"Dear Client,
as requested we have checked your drives. Both drives pass a test without any…
captain lizard
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17
votes
4 answers
explain md's raid10,f2
I know how most of the various RAID's work. But I stumbled on the recommended raid10,f2
mode while researching linux software raid. I don't really understand how it works on 2 or 3 disks. could someone explain it to me? or point me to a really good…
xenoterracide
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16
votes
3 answers
How do I list which drives are part of each RAID array?
I have a linux software RAID using md. I want to list all of my RAID arrays and each hard drive attached to them. Is there an easy way to do that?
fatal_error
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16
votes
4 answers
Linux mdadm software RAID 6 - does it support bit corruption recovery?
Wikipedia says "RAID 2 is the only standard RAID level, other than some implementations of RAID 6, which can automatically recover accurate data from single-bit corruption in data."
Does anyone know if the RAID 6 mdadm implementation in Linux is one…
sa289
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15
votes
3 answers
mdadm - Remove disk from RAID0
So, I'd like to know, is is possible to do the following with mdadm:
I start with RAID0 configuration on 2 disks: sda and sdb.
I would like to add one more disk to array, sdc and move all data from sdb to it.
Disconnect sdb.
Right now I see only…
maniaque
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15
votes
3 answers
mdadm raid5 recover double disk failure - with a twist (drive order)
Let me acknowledge first off that I have made mistakes, and that I have a backup for most but not all of the data on this RAID. I still have hope of recovering the rest of the data. I don't have the kind of money to take the drives to a recovery…
Peter Bos
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15
votes
2 answers
Verify A Partition is Aligned in Linux With RAID and LVM
Does anyone know the steps to verify that a XFS filesystem on top of LVM and md RAID is properly aligned on an array of 4096 Byte aka "Advanced Format" sectored disks?
Some references…
Kyle Brandt
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15
votes
2 answers
Unable to mount an XFS filesystem from Linux RAID6 array ("Log inconsistent")
First time poster - my apologies if I don't get the etiquette correct.
I have a ~200TB RAID6 array with 30 disks and I'm unable to mount it - I just get the message:
mount /dev/md125 /export/models
mount:/dev/md125: can't read superblock
If I run…
Bob
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14
votes
2 answers
How to recover an mdadm array on Synology NAS with drive in "E" state?
Synology has a customized version the md driver and mdadm toolsets that adds a 'DriveError' flag to the rdev->flags structure in the kernel.
Net effect - if you are unfortunate enough to get a array failure (first drive), combined with an error on a…
Nathan Neulinger
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