RAID stands for redundant array of independent disks, and allows for disks to be linked in various ways. Common RAID setups in Ubuntu are a hardware RAID, FakeRAID and software RAID.

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Ubuntu can't mount swap from RAID1

I have just built a new server to host a minecraft server. I have two hdds that are in hardware raid 1, and I have installed Ubuntu Server 11.04 on those disks. My problem is that anytime I reboot I ...
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Why can't Ubuntu 11.04 installer see all my partitions?

In February last year, I built a new PC from parts. Fast foward 16 months, and I'm repeatedly cleaning malware infections from Windows 7. I decided to try Ubuntu on my PC. My PC has hardware raid. ...
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How do I get a new drive integrated into my software RAID?

When I first installed Ubuntu a couple years ago, I set it up with a software RAID using the Ubuntu alternate install disk. I have two 500 GB drives in the RAID. A few days ago, one of the drives ...
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348 views

Degredation test of RAID 1

I have just configured two hard drives with RAID1 via an ubuntu 10.4 installation. It is installed to boot in degraded mode. I want to disconnect the power from the one drive and have it boot, and ...
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are there any issues creating a tmpfs mount when my root partition is a RAID5 array

I have a new Ubuntu 11 server install created per the wiki with the following partitions: md1 : active raid5 sdc5[2] sda5[0] sdb5[1] 1935813632 blocks super 1.2 level 5, 512k chunk, algorithm 2 ...
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Switching mdadm to an external bitmap

I've just read this in another post about improving RAID5/6 write speeds: After increasing stripe cache & switching to external bitmap, my speeds are 160 Mb/s writes, 260 Mb/s reads. :-D ...
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611 views

Installing 10.04 server on HP xw9400 Workstation with RAID 5

I have a workstation that was given to me that is a friggen powerhouse, so I figured I would set it up as my development and demo server. This is my first experience installing Ubuntu onto a RAID ...
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How does btrfs RAID work in degraded mode?

My idea was that (using loopback devices) it works like this Create the raid array sudo mkfs.btrfs -m raid1 -d raid1 /dev/loop1 /dev/loop2 You mount them sudo mount /dev/loop1 /mnt and mark them ...
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How do I configure my 2 RAID drives so I can use it as /home?

I've installed Ubuntu 11 64-bit to a 2 TB drive. It is on /dev/sda - port 1 of SATA Host Adaptor. This contains /dev/sda1 (1 MB boot), /dev/sda2 (2TB EXT4), /dev/sda3 8.6GB SWAP. I also have: ...
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Delete mdadm array but keep data

I have a two-disk mdadm RAID1 array. One of the disks has died so the array is in a degraded state. It's been like this for a while and while I didn't mind getting the occasional email through, ...
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How do I improve my server disk performance

I have an HP Microserver running Ubuntu 10.04 LTS. It's a low power server with 5 internal drive bays. I use it to backup my remote servers, VPSs and local laptops over the network. I want to get the ...
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Possible/viable to make a btrfs RAID between SSD and HDD?

Since I don't use my laptop's CD-drive I want to put a small (8 GB) SSD into the CD-drive slot (I'll use a caddy similar to this one). I want to use compressed btrfs on the SSD and put all the data on ...
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Dual Boot Ubuntu 11.04 / Vista 32 with a RAID 0

I tried to install Ubuntu 11.04 several time using all the informations I could gather on the web. But I still fail to install it, and as my Vista partition contains very important informations I ...
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2k views

Testing my raid array / is my mdadm raid working OK? [duplicate]

Possible Duplicate: MDADM Superblock Recovery This may just be me being very stupid but I don't get it! I am new to mdadm raid configuration and my system configuration is as follows: 1 * ...
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1answer
751 views

How do I fix a slow boot on a RAID setup?

I've just finished setting up a RAID 1 on my system. Everything seems to be okay, but I have a very slow boot time. It takes about three minutes between the time I select Ubuntu from GRUB and the time ...
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How do I install GRUB on a RAID system installation?

I'm trying to setup and install Ubuntu on a RAID 1 setup. I have two disks, sdb and sdc. I've been following this guide https://help.ubuntu.com/community/Installation/SoftwareRAID which more or less ...
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668 views

Fake RAID (dmraid) not seeing new SATA drives

I have three drives in my machine, one SSD with 32GB and two 1TB drives, attached to an Intel 82801JI (ICH10) SATA AHCI Controller. The problem is, that I can access only one of the 1TB drives when ...
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How to install and boot on a RAID 5 Configuration?

I've been trying for a couple of days now to get Ubuntu 10.10 installed on a RAID 5 setup. I have 3 1TB drives so I also need Ubuntu to boot off of one of those drives. From what I've been able to ...
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What does “md value mismatch_count” count?

Since upgrading to 11.04 I have been trying to get my 5 disk RAID5 array back online. The array was initially split in two, I tried to use a create command with the assume clean option to get it back ...
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2k views

Resilience of Btrfs inside RAID5

Btrfs currently lacks fsck, risking corruption if there's a power failure. To what extent, if at all, would creating a btrfs filesystem within a RAID5 array mitigate this?
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How do I recover my RAID partition after the Ubuntu 11.04 upgrade?

My RAID drive was working well with Ubuntu 10.10, but after doing an upgrade I am no longer able to mount my RAID drive. I think it is due to a invalid RAID description similar to this problem: ...
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How do I recover my RAID partition after the Ubuntu 11.04 upgrade? [duplicate]

Possible Duplicate: How do I recover my RAID partition after the Ubuntu 11.04 upgrade? My RAID drive was working well with Ubuntu 10.10, but after doing an upgrade I am no longer able to ...
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494 views

How to mount FakeRAID to /home of a new system?

I'd like to know how to re-mount the FakeRAID disk to the new system safely so that I won't losing my data. I'm going to install ubunto10.10 to root My old computer setting: 1 320G Disk for / 2 ...
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17k views

“Special device does not exist”

I have 3 hard drives in my machine. Two of them are 1TB drives with my old home partition on a software RAID1. I installed an SSD as a 3rd drive with a fresh Ubuntu 10.10 currently running. I now try ...
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698 views

Ubuntu Server installation command mode - cfdisk command not found

I'm trying to install Ubuntu 10.04 server with LVM+RAID. However, when I use cfdisk command to create new partition, I received the message: /bin/sh: cfdisk: not found. Please advise me. Thanks.
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How do I install Ubuntu 10.10 beside Windows 7 onto a fake raid?

I currently have 4 drives setup in Raid 10. I've tried installing Ubuntu straight to the metal but it does not recognize my Windows partition and upon quitting the installation and then restarting, my ...
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2k views

error: no such device: GUID

I have an old(er) machine that I'm trying to wipe out and install ubuntu 10.04. The machine has 4 500GB HDDs that were previously set up as a raid. When I run the installer, it asks if I want to ...
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How to migrate installed system to RAID1?

I have home server (Ubuntu Server 10.04) which boots from single 80Gb HDD drive, now I want to make it boot from 2x500Gb RAID-1. I've already successfully created it through MDADM. But how can I move ...
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868 views

RAID 10 not being found by installer

I had ubuntu installed with raid 0 enabled. I have added 2 more disks went into the bios deleted and created a new raid setup using raid 10 (total of 4 disks now). However during install of ubuntu ...
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1answer
2k views

How to access a fake raid?

I have a fake raid, which I wanted to access using mdadm /dev/md0 -A -c 128 -l stripe --verbose /dev/sda /dev/sdc which should be right, as far as I understand the man page. But I get the message ...
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791 views

Did I lose my RAID again?

A little history: 2 years ago I was really excited to find out that mdadm is so powerful that it even can reshape arrays, so you can start with a smaller array and then grow it as you need. I've ...
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RAID slow on all levels

I am getting very slow write speeds (<1MB) with RAID 1 and RAID 0 (striping and mirroring). The read speeds are sufficiently fast but writing is very slow. At first I thought it was just poor ...
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732 views

Raid md device is not remove from memory, how to overcome this problem

I create raid 10 , i removed two arrays form md11 one by one , after that i going to editing the contents those are mounted ( it will be not responding stage), after i try for remove arrays those are ...
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1answer
655 views

Is Error Recovery Control or TLER necessary for software RAID5 using LVM

I ave been told that for RAID configurations you don't what to use standard desktop drives because they when/if they enter a error recovery mode they might time out and get dropped from the raid. Is ...
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Well supported Hardware Raid Controller

I am currently planning to buy a hardware-raid controller. This became necessary since I am running Linux and Windows in parallel and now need the redundancy for both OS (Im am going to use RAID1 / ...
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500 views

AMD Raid SMART Tests Ubuntu Server

I have an AMD SB with Raid 1 set up through that. I installed Ubuntu Server with no problems. However I know through windows one can set up SMART Tests with AMD's software. Is there a way to run SMART ...
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Should I disable write cache in an mdadm array?

My gut says disabling write cache on soft RAID5 is the smart move, but I'm not certain. Possible Considerations: The drives a WD20EARS with 64Mb cache. The server hasn't gone down due to a power ...
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Using btrfs in RAID arrays and partitioning

Probably stupid questions but here goes: Can btrfs use only a portion of a HDD in a raid "array"? I have 3 HDDs: 80GB, 160GB, and 200GB external USB. I want to put root+boot in the first 20GB of the ...
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1answer
5k views

Is a disk/ata timeout exception dangerous?

I have a few hard drives in mdadm RAID 5 configured to go to standby after a few minutes of inactivity. (Using hdparm.conf spindown_time.) At irregular intervals I get messages like these in dmesg: ...
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How do I know what physical drives/partitions are behind my /dev/mapper/isw_dghbbcaabe_RAID_Volume11?

This is a just upgraded Ubuntu 10.04.1 LTS machine. The /dev/mapper/isw_dghbbcaabe_RAID_Volume11 is "new" to the upgrade but I don´t know what physical drives/partitions are included in the "device". ...
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Why can't Ubuntu find an ext3 filesystem on my hard-drive?

This question is related to this question: Not enough components to start the RAID array? I'm trying to retrieve data from a "Western Digital MyBook World Edition (white light)" NAS device. This is ...
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Not enough components to start the RAID array?

I'm trying to retrieve data from a "Western Digital MyBook World Edition (white light)" NAS device. This is basically an embedded Linux box with a 1TB HDD in it formatted in ext3. It stopped booting ...
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2answers
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Restoring GRUB2 on Software RAID 0 using LiveCD after Windows 7 wiped it

I have installed Ubuntu 10.10 on my system. However, I need to install Windows 7 back, and I expect that it would alter GRUB and it did. Right now, my partition on my Software RAID 0 looks like this: ...
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Improving mdadm RAID-6 write speed

I have a mdadm RAID-6 in my home server of 5x1Tb WD Green HDDs. Read speed is more than enough - 268 Mb/s in dd. But write speed is just 37.1 Mb/s. (Both tested via dd on 48Gb file, RAM size is 1Gb, ...
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How to fix boot message [RAID partition] not ready yet? [duplicate]

Possible Duplicate: mdadm: breaks boot due to “is not ready yet or not present” error I've got a RAID 5 setup for my /home partition. Every two to three boots my hdisks don't ...
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1answer
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How do I unmark a “failed” md device?

In an effort to clean up from a software bug in md, I marked half of a RAID (/dev/sda1 and /dev/sdb1 in RAID1) as faulty using: mdadm /dev/md2 --fail /dev/sdb1 mdadm /dev/md2 --remove /dev/sdb1 But ...
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How to access MD RAID via Live CD?

We are currently trying to run access the data on a server running a HP Ml110 G5 SATA raid controller, using the latest Ubuntu Live CD. We need to delete a few files to let the server boot into ...
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2answers
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Rebuild mdadm Raid5 after OS hard drive died

I have an ubuntu desktop 10.4 "server" with 5 hardrives. 1 of the hardrives had 3 OS's on it (Windows Vista, Windows XP, and Ubuntu 10.4). I primarily used the ubuntu OS so that I could use mdadm and ...
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How can I physically identify a single drive in a RAID array?

I have an external drive bay with 4 eSATA disks in it. My system has a 4-port eSATA card, as well as a pair of internal hardware RAID1 drives. The external drives are in software RAID1 pairs as ...
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Mdadm seems to have completely forgotten about a device and shrunk my array

After a bit of investigating of a problem I've just encountered, it looks like mdadm has completely forgotten about a new device I'd added to an array. I recently added a new device to the array which ...