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.

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22
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3answers
56k views

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 raid1, going to raid5 once I have more drives (and ...
1
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0answers
25 views

How should I approach designing my btrfs pool/s? [on hold]

I am vaguely familiar with a few COW/modern filesystem concepts, and am nowhere near an expert or even beyond neophyte status when it comes to btrfs. I've just installed Rockstor on a machine I intend ...
1
vote
2answers
718 views

Can I mount a microsoft mirrored dynamic disk?

I'm testing out sw raid in windows 7, but I almost always use linux and I would like to know if it's possible to mount such a mirrored dynamic disk. I can already mount each members separatly but ...
0
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1answer
13 views

How to automatically check for failed hard drives in RAID array?

We've got a couple of servers in-house containing hardware RAID5 and RAID6 arrays with 8-15 disks each. What's the easiest way to automatically check for failing hard drives using a script so that ...
2
votes
1answer
24 views

Using a larger drive in a RAID 1 setup

Is it possible to introduce in a RAID 1 setup a larger drive using its free space for further uses? E.g: What we have: sda - 250 GB HD |-- sda1 - /boot |-- sda2 - / sdb - 500 GB HD |-- sdb1 - ...
4
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3answers
120 views

Software RAID 5 and 6 stripe size: why smaller is less efficient?

I read here and then that small stripe size is bad for software (and maybe hardware) RAID 5 and 6 in Linux. The rare benchmarks I saw fully agree with that. But the explanation given by everybody is ...
1
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1answer
25 views

mdadm raid filesystem differs from disk filesystem

I have created a raid 5 using mdadm on Debian. I used 2 new and 1 "old" disks. The old one had ext3 before. Using "parted -l" I noticed the raid has ext4 as filesystem but the old disk has ext3. I ...
0
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1answer
58 views

File transfer between SSD and RAID array uber-slow

It's really simple: this server has an SSD for the main drive, and a RAID array (mdadm) for storage. Intermittently, it has a problem writing to the array: the write speeds slow down to the point ...
2
votes
2answers
45 views

High IO wait - How to determine the root cause?

I have a MySQL instance on two dedicated servers. One for the production, the other for the test platform. The 2 servers are pretty the same, the only difference is the RAID controller and the ...
2
votes
1answer
110 views

Wheezy to Jessie update broke root software RAID, can it be fixed?

Last night I attempted to update my PC from Debian 7, Wheezy (now old stable), to Debian 8, Jessie (now stable). On rebooting, the system broke at 0.267166 minutes into the launch telling me it can't ...
1
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2answers
30 views

New RAID array will not auto assemble, leads to boot problems

I had just asked this question where I was unable to boot after installing a new RAID1 Array. I was able to get to the terminal, but once I sorted that out I realized that my problem isn't so much an ...
1
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0answers
8 views

Shrinking root partition on Debian

I'm using a headless Debian Wheezy server with 2x3TB disks. It was installed automatically with RAID1. This is the output of df -h: $ df -h Sys. fich. ...
1
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2answers
29 views

How do I migrate a RAID system to a larger set of HDDS?

All the posts I've found are about moving to new machines or migrating an entire OS from one HDD to another. I don't really know what the hell I'm doing, but I'm apparently the Linux expert. We ...
1
vote
1answer
18 views

How do I prepare new drives for use in software raid?

Normally, I create RAID arrays during installation, but I'm trying to add an array to an existing system. The OS (Mint16) is on its own drive. I've added two brand new physical drives to the machine, ...
2
votes
3answers
35 views

mdadm refuses to add second identical disk to array

I have a RAID 1 array which is in a degraded state and want to add another drive to it. # mdadm --detail /dev/md1 /dev/md1: Version : 1.2 Creation Time : Fri Mar 21 17:23:00 2014 Raid ...
2
votes
1answer
28 views

data recovery after partial shred

well i issued the following command: shred -v /dev/sdb. However I wanted to shred /dev/sda. I realized my mistake after about 2gb had been shredded (out of 2.7tb raid volume). what is the ...
3
votes
3answers
111 views

Software RAID 10 Array Space Loss

I purchased a dedicated server from a hosting company for a forum I am starting and the drives are configured as 4 x 64GB SSD's in a RAID 10 software array. The total amount of space I was expected ...
1
vote
0answers
30 views

change device names in LVM

We have a server crash situation for our Oracle Database Server. The operating system was SLES 10 SP2 and Oracle Release 11.1.0.6.0. Now the system had this setup before crash. 1 boot disk --- ...
3
votes
1answer
1k views

Proxmox Master Node crashes

I've inadvertently discovered a Proxmox bug. I run a personal cluster of 4 nodes (a technology lab for giggles and gags). Each node has a Dell Perc 5i and 4 HDDs in RAID 10. The standard Proxmox ...
1
vote
1answer
1k views

Problem with former RAID hard drive settings in Linux Mint 17

I'm new to Linux, just installed Linux Mint for the first time. I have two hard drives which were previously in a RAID configuration. Now before I have installed Linux I've changed them to individual ...
0
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0answers
26 views

ZFS Mirror on same drive for redundancy?

The device I would like to use as a home server has only a single 2.5'' internal hard drive bay currently fitted with 1TB. The actual data storage (2x 1TB) will be attached to the external USB 3.0 ...
0
votes
1answer
28 views

No Raid feature in Redhat Hypervisor

We purchased Supermicro Server "SUPERMICRO CSE-827H-R1400B" . And each of its node has 9TB Storage . And we planned to use this server as a Host for Virtual Machines. So i started to install the ...
2
votes
1answer
96 views

Resize MDADM/Software RAID underlying partition and filesystem

I am running out of space on my root partition and would like to steal some from a different partition. The drives are 2x120GB with mdadm software RAID. I am using CentOS 6.5 64-bit. I used the centos ...
1
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0answers
22 views

BTRFS - removing drive by devid instead of path

I recently lost a 5 TB drive using btrfs. I had a system freeze (unsure why) while a balance was running. My SMR drive got corrupted. I was able to mount my array degraded and balance my data. ...
1
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1answer
38 views

How to prevent UDEV rules assigning a device to a specific set of names

I have some UDEV rules for a RAID array; 10 hard disks are assigned names from /dev/sda to /dev/sdj. The disks can be absent at any time. How do I write a UDEV rule to prevent a device such as an ...
0
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0answers
16 views

One disk in RAID setup high usage

I have a system here with 6 disks all same make and model, and on that I have 3 partitions. / RAID 6 /var/log RAID 6 /storage RAID 5 on / I created a swap file instead of partition. With ...
0
votes
1answer
34 views

Where to install GRUB?

I am running Ubuntu 14.04 on a remote server. It's the only OS installed. I need to be super-cautious before rebooting the machine since KVM access to the server is quite tricky. During a GRUB ...
1
vote
1answer
66 views

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 ...
2
votes
1answer
55 views

proper way to stop software RAID before system shutdown

This should be straightforward, but I have been unable to find a direct answer by searching. I find that if I unmount an mdadm-managed array and then either (1) unplug the array, (2) power off the ...
1
vote
1answer
69 views

ZFS Raid or Hardware Raid in FreeNAS

We bought SuperMicro server "SUPERMICRO CSE-826E16-R1200PB" which will be used for storage. Total HDD 10 - 4TB Seagate HDDs 2 - 60 GB SSDs Now im planning to install FreeNAS on it . And i will ...
0
votes
2answers
54 views

Raid devices are mounted with different UUID

Centos 7.1 64. This is what I have: Two raids, but not md0 and md1 [root@localhost]# cat /proc/mdstat Personalities : [raid1] md126 : active raid1 sdb2[1] sda2[0] 974711616 blocks super 1.0 ...
0
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2answers
47 views

Debian : Mounting a raid array

I have a Debian system on which we migrated to a SSD for faster execution. Before that we had a 2.0Tb hard disks in RAID. Now we want to use the RAID drives to perform storage generated by the ...
3
votes
1answer
824 views

cleaning /dev/md0 filesystem ( raid) [closed]

I have a CentOS server using raid. The /proc/partitions contains: major minor #blocks name 8 0 976762584 sda 8 1 104391 sda1 8 2 921600855 sda2 8 3 55054755 ...
3
votes
0answers
143 views

Running a btrfs RAID 5 array on Arch Linux

For two weeks, I've been trying to run my Raspberry Pi (model B) as root from a btrfs RAID 5 without success. The RAID runs on three 1TB disks /dev/sda, /dev/sdb and /dev/sdc. The three disks were ...
0
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0answers
55 views

Install of manjaro linux on Raid 0

Im trying to install gnome manjaro on my raid 0 ssd's along side my uefi windows 8. The GUI installer proceeds without problems but when I try to boot the system gets stuck on the manjaro load screen. ...
3
votes
1answer
185 views

RAID6 scrubbing mismatch repair?

You can initiate a scrub of a mdadm array with echo 'check' > /sys/block/mdX/md/sync_action, and if a bad sector is found, it'll rewrite it automatically (from a mirror or from parity information ...
4
votes
2answers
107 views

mdadm - Can't Remove Components In RADI1

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, ...
5
votes
4answers
6k views

Mounting multiple devices at a single mount point on Linux

Is there a way to mount multiple hard drives to a single mount point? Let's say I run out of space on /home and decide to add an extra hard drive to the computer. How do I scale the space on a mount ...
0
votes
1answer
122 views

Required GRUB modules for booting on mdadm RAID1

I have a mdadm-managed RAID1 with a single EXT4 partition on it (having both the OS files and GRUB's files in /boot/grub), and I'd like to know what modules and what configuration do I need for GRUB ...
0
votes
1answer
642 views

mdadm RAID 5 and parted unrecognized disk label

I have three 3 TB drives that I am attempting to put together into a RAID 5 setup with mdadm, but I am running into some issues. (Actually, I have four 3 TB drives I will be using, but one of them ...
11
votes
2answers
3k views

bit rot detection and correction with mdadm

I'm about to re-organise all my HDDs in my 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 ...
1
vote
1answer
115 views

Repairing a RAID5 array

For a friend I'm trying to repair a RAID5 array, consisting of 3 2TB disks. After working perfectly for quite some time, the computer (running Debian) suddenly wouldn't boot anymore and got stuck at a ...
0
votes
0answers
115 views

encrypted btrfs RAID1 array fails to mount at boot - open_ctree_failed

I have an encrypted btrfs RAID1 array set up as my /home directory on a fresh install of Linux Mint 17.1. At the Plymouth screen during boot, I enter my password for the two drives, and then receive ...
2
votes
2answers
62 views

Disassemble a RAID 1 arragement without removing/reinstalling the system

I've set up a Soft Raid 1 using Debians built in RAID systems. I set up the raid because I had a space HDD when I set up the server and thought why not. The RAID is set up using what-ever Debian did ...
1
vote
1answer
29 views

Storing documents and backups on several different drives

Currently I have Ubuntu installed on a 120GB SSD. However I also have 3 more hard drives installed on the computer, 2 x 640GB in aRAID array and a 60GB SSD. What I am trying to achieve is to use the ...
0
votes
4answers
65 views

RAID 1 on server - need file from mirrored drive

About 3yrs back I had setup an Ubuntu server for a medical clinic. I had set in 2 HDD's for the purpose of having RAID 1 (software RAID) Today suddenly they can't access a table on one of the mySQL ...
3
votes
1answer
211 views

vPrevent Debian from auto-assembling raid at boot

I set up a Debian wheezy (7.6), installed openmediavault, and created a software raid 5 with that. It is listed at /dev/md127. Now I want to move that to a virtual XEN VM. To do so, I have to stop ...
4
votes
2answers
5k views

Strange error message during CentOS 6.5 installation regarding disk containing BIOS RAID metadata?

While attempting to use an old 40GB HDD to setup a kind of junky though usable Athon 1GHz system I ran into the following error during the HDD identification/partitioning phase of the installation: ...
0
votes
0answers
42 views

HW RAID10 without TRIM support with SSD

Recently we purchased new server for Database with 1TB x 4 SSD in Hardware RAID 10, but my Hardward RAID doesn't support TRIM so you think it is going to be big deal? Is there anyway i can do ...
4
votes
1answer
196 views

How mdadm recognizes which device is right one to sync others with

Imagine you have mdadm raid1 with 2 disks. Then you turn off the server, split the disks each one to different machine and boot both of them, so they will become slightly inconsistent Now you turn ...