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Questions tagged [mdadm]

A linux utility used to manage software RAID devices.

844 questions
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Remove "faulty state" in RAID 1

I wonder if there is any possibility to remove the state "faulty" in a RAID 1 if (for example) someone failed the wrong hard disk. I already searched for answers with Google and found several tutorials with re-creating the array and adding…
thonixx
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Ubuntu server, gpt partition table, mdadm, grub boot fail

Basic working system details: I used the Ubuntu 12.04 server CD to install a server. I have 4 disks. On all disks I did the following, similar to this howto : created a 2GB swap partition created a 256 GB /boot partition created a 64 GB RAID10…
Peter
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Is it safe to shutdown a machine while rebuilding/recovering/growing a RAID5 array that was built with mdadm

I have recently started a recovery on my 5-drive RAID in my file-server, and it says it'll take 691+ minutes to complete. I was wondering what would happen to the process if the machine lost power - say in a blackout? Would I need to restart the…
jsnfwlr
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RAID-1 to RAID-5 using mdadm

As per subject. When converting from RAID-1 to RAID-5 using mdadm, why must a RAID 1 array contain 2 devices and not more than 2 devices? I don't understand RAID strong enough to pinpoint a reason. Background: My three RAID-1 arrays contain 3…
stampkick
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How do I troubleshoot my RAID array?

I just checked into my RAID array this morning and what I got is: $ cat /proc/mdstat Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10] md1 : active raid1 sdc7[0] 238340224 blocks [2/1] [U_] md0 : active…
stdcerr
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Linux Software RAID10: Mysterious renaming /dev/md0 to /dev/md127: Why?

During the last two nights we had mysterious events on a server running Ubuntu Linux 12.04 LTS with a Linux mdadm software RAID10: DeviceDisappeared /dev/md0 NewArray /dev/md127 Both messages appeared in the same second, on the same time as the…
pefu
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mdadm --zero-superblock on disks with other partitions on them

I have three disks which used to hold an MD RAID5 array. I have since removed (or so I thought) this array and created partions for btrfs and swap space. On rebooting the machine, MD still binds the devices that used to hold the old array, causing…
Simon Lindgren
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mdadm: Which disk is being rebuilt?

I noticed my software RAID1 degraded, and wanted to figure out which of the two disks in the array is being rebuilt/re-synced since they both show as being up. I am hoping someone can shed some light on this, if it's even possible to figure out…
Paul
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DegradedArray event on /dev/md1

This morning I got this message: This is an automatically generated mail message from mdadm running on A DegradedArray event had been detected on md device /dev/md1. Faithfully yours, etc. P.S. The /proc/mdstat file currently contains the…
user1821484
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Can I create a "soft" RAID1 array without nuking data?

I've just bought two 1.5TB disks with the aim of creating a 1.5TB RAID1 array. In my infinite lack of wisdom (and a lack of space inside the computer - it already had 6 disks), I stuck one in, formatted it to EXT4 and proceeded to copy data all over…
Oli
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apt-get update mdadm scary warnings

Just ran an apt-get update on one of my dedicated servers to be left with a relatively scary warning: Processing triggers for initramfs-tools ... update-initramfs: Generating /boot/initrd.img-2.6.26-2-686-bigmem W: mdadm: the array /dev/md/1 with…
user568829
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What tells initramfs or the Ubuntu Server boot process how to assemble RAID arrays?

The simple question: how does initramfs know how to assemble mdadm RAID arrays at startup? My problem: I boot my server and get: Gave up waiting for root device. ALERT! /dev/disk/by-uuid/[UUID] does not exist. Dropping to a shell! This happens…
Brad
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Using 4k drives with md/LVM/dm-crypt

I know that I have to align my 4k drives by a multiple of 8 sectors, but what about md-RAID / LVM / dm-crypt? How do I tell these layers that my drive is 4k? If they don't respect the 4k sector size, the partition alignment is useless. How do I…
Vincent
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Linux Software Raid 10 hung after 1 drive failed, mdadm will not let me force remove the faulty device

I have a Linux software raid 10 setup consisting of 5 RAID 1s (Two drives per mirrored setup) and a RAID 0 across all 5 RAID 1 pairs. To test that none of the drives were going to fail quickly under load I used badblocks across the RAID 0 with a…
ScottZ
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How to delete removed devices from a mdadm RAID1?

I had to replace two hard drives in my RAID1. After adding the two new partitions the old ones are still showing up as removed while the new ones are only added as spare. I've had no luck removing the partitions marked as removed. Here's the RAID in…
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