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Questions tagged [raid]

RAID - Redundant Array of Independent Disks. A Storage technology to provide redundancy and performance, to reduce I/O bottlenecks involved in using multiple disks for large storage.

The basic idea of RAID was to combine multiple small, independent disk drives into an array of disk drives which yields performance exceeding that of a Single Large Expensive Drive (SLED). Additionally, this array of drives appears to the computer as a single logical storage unit or drive.

More at Wikipedia : http://en.wikipedia.org/wiki/RAID

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How to check 'mdadm' RAIDs while running?

I'm starting to get a collection of computers at home and to support them I have my "server" linux box running a RAID array. Its currently mdadm RAID-1, going to RAID-5 once I have more drives (and then RAID-6 I'm hoping for). However I've heard…
djsmiley2kStaysInside
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RAIDing with LVM vs MDRAID - pros and cons?

In his answer to the question "mixed raid types", HBruijn suggests using LVM to implement RAID vs the more standard MDRAID. After a little investigation, it seems LVM also supports RAID functionality. In the past, I have used LVM on top of MDRAID,…
Faheem Mitha
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New md array is auto-read-only and has resync=PENDING

I've created a new md array with the following command: mdadm --create /dev/md1 -l 1 -n 2 /dev/sd[ed]1 But now /proc/mdstat shows the array as "auto-read-only" with resync=PENDING: ~ # cat /proc/mdstat Personalities : [raid1] md1 : active…
Martin von Wittich
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Can I create a software RAID 1 with one device

I have a single disk that I want to create a mirror of; let's call this disk sda. I have just bought another identically-sized disk, which we can call sdb. sda and sdb have one partition called sda1 and sdb1 respectively. When creating a raid, I…
whoami
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What's the difference between mdadm state "active" and state "clean"

I have two different computers with different RAID5 arrays. When I run the command mdadm --detail /dev/md0 one drive reports "active" while the other reports "clean" for the "state" field. What is the difference? Should I worry about either…
Daniel
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Remove drive from soft RAID

I have a dedicated server with 3 SSD drives in RAID 1. Output of cat /proc/mdstat: Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10] md4 : active raid1 sdc4[2] sdb4[1] sda4[0] 106738624 blocks [3/3]…
Raul
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bit rot detection and correction with mdadm

I'm about to re-organise all my HDDs in my home linux box nas and would like to use mdadm raid for data protection and its flexibility for reshaping the arrays. However, before I use mdadm for this I'd like to know how it handles bit rot. …
BeowulfNode42
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How to get details of RAID devices both soft and hard?

I want to check if my server has RAID configured both soft and hard. I tried some commands on my server (Suse Enterprise Edition 11): **ms:~ # cat /proc/mdstat Personalities : unused devices: ms:~ #** I tried to execute raiddev /dev/md0 but…
Özzesh
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How to mount a disk from destroyed raid system?

I have a horrible situation where I have to restore data from damaged raid system in a rescue Debian Linux. I just want to mount them all to /mnt/rescue in read only modus to be able to copy VMWare GSX images to another machine and migrate them to…
Tony Stark
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Using mdadm --examine to write mdadm.conf

I'm trying to script the RAID setup for a (growing) number of identical servers. The advice I've seen for using mdadm suggests that once the RAID array has been created you can run mdadm --examine --scan >> /etc/mdadm.conf so that the array is…
David Waller
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mdadm: can't remove components in RAID 1

I have my /boot partition in a RAID 1 array using mdadm. This array has degraded a few times in the past, and every time I remove the physical drive, add a new one, bring the array being to normal, it uses a new drive letter. Leaving the old one…
Sajan Parikh
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Mount a single hard disk that was part of RAID 1

So I had a RAID 1 with two hard disk. One hard disk failed, then I replaced it and I reinstalled on this new hard disk a fresh Linux. Now If I type fdisk -l I get: root@ns354729:/mnt/sdb2# fdisk -l Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255…
giò
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Linux: LUKS and multiple hard drives

I have a Debian Linux system (amd64) installed on a RAID-1 system encrypted device (LVM on LUKS) and will have a RAID-6 of >=4 disks where I'll put my data (LUKS and maybe LVM). I think the basic idea is to unlock the system encrypted partition (at…
user51166
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How to assemble a specific RAID array without using /etc/mdadm.conf

Is it possible to assemble a specific RAID array using mdadm and its scan-functionality, but without the need for a configuration file? Background: I'm using a custom-made initramfs to setup my system (dm-crypt and other stuff). Everything is done…
maxxim
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Problem Installing UBUNTU 14.04 (AND Mint 16, which is based on UBUNTU 13.10) as dual boot on RAID 0 with Windows 8.1

Ok, I know that there is https://askubuntu.com/questions/455511/dual-boot-ubuntu-14-04-and-windows-7-on-fakeraid-installation-error-question-m#new-answer?newreg=f2b8bde40c8947f8ac8e3cedec0d1964 and that that post has some answers for me, but I…
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