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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How can I quickly copy a GPT partition scheme from one hard drive to another?

On a non GPT partition table I can do sfdisk -d /dev/sda | sfdisk /dev/sdb. But sfdisk doesn't support GPT partition tables. What can I use instead? I'm looking for a one or two command solution, ...
23
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4answers
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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 ...
13
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4answers
38k views

How do I align my partition table properly?

I am in the process of building my first RAID5 array. I've used mdadm to create the following set up: root@bondigas:~# mdadm --detail /dev/md1 /dev/md1: Version : 00.90 Creation Time : Wed ...
13
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4answers
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Installing 12.04 server as a software RAID 1 mirror fails to boot

I'm installing a few new Ubuntu Server 12.04 LTS servers, and they have two 512 GB SSDs. I want them to use software RAID 1 mirroring, so I was following this document religiously step by step: ...
10
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7answers
17k views

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 ...
10
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1answer
3k views

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 ...
9
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4answers
31k views

Ubuntu 12.04 installer does not see Windows already installed on my computer [closed]

When I just tried to install Ubuntu 12.4 alongside Windows 7 on my new "HP Pavilion 64k desktop with Windows 7" computer, Ubuntu said this computer has no detected operating system and someone ...
8
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2answers
3k views

Do I have to worry about “error: superfluous RAID member”?

When running update-grub on the newly installed Ubuntu 12.04 with an older software RAID (md), I get: error: superfluous RAID member (5 found). error: superfluous RAID member (5 found). Generating ...
7
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5answers
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How do I rename an mdadm raid array?

For some reason, when I try to rename an mdadm raid array to a textual name, the change doesn't take. I tried the advice from this serverfault question, but to no avail. ~$ mdadm --version mdadm - ...
7
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4answers
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Is having the 'swap' partition at the 'beginning' better than at the 'end'?

I recently installed Ubuntu 11.04 onto a RAID0(stripe) device using the alternate installation disc and manually partitioned the HDs ext4 and swap partitions; during this process, I was reading in a ...
7
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1answer
16k views

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 ...
7
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4answers
11k views

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 / ...
7
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2answers
6k views

How to implement RAID 1?

How to set up RAID 1 [software, hardware or fake] on Ubuntu 12.04 desktop?
6
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2answers
8k views

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 ...
6
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2answers
2k views

Is there a Linux software RAID that can be shared with a windows installation?

What are the options I've got when it comes to RAID and Windows?
6
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1answer
4k views

How to set up SSD raid and TRIM support?

I am looking to set up a new server. I can only use Intel 520 Series 240gb MLC ssds or standard Seagate 7200rpm disks. These are the non negotiable options. Naturally, as this is going to be running ...
6
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4answers
786 views

Wubi doesn't start, with a “cannot mount /dev/dm-3” error

I installed Wubi here, but when restart the pc I got the following screen: And this "command line" "initramfs". How do I preceed from here? --update By the way, looks like my HD is raid. Not ...
5
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2answers
5k views

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 ...
5
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3answers
7k views

Megaraid SAS Raid Controller

I have about half a dozen servers all running the Intel RS2BL080 raid controller on Oneiric server AMD64. It works fine using the megaraid_sas kernel module but when I try to use megacli to probe the ...
5
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2answers
12k views

Setting Up RAID During 13.04 Install

I am attempting to install Ubuntu 13.04 Desktop on RAID 5, but I can't figure out how to do it. I have read that it can be done during the install, though I haven't found a good explanation of how ...
5
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2answers
12k views

Put HDDs in standby after X minutes using hdparm doesn't work

I use Ubuntu 12.04 on a home server. There are 5 hard drives: one SSD with the OS and 4 HDDs (Samsung HD204UI) configured as a RAID5 using mdadm. I don't need the RAID very often (say, about once per ...
5
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1answer
13k views

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 ...
5
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1answer
20k views

Software raid - mdadm - re-find my array

Description Today I plugged in another hard drive and unplugged my raid drives to ensure when I wiped the drive, I would not accidentally pick the wrong drives. Now that I have re-plugged in my ...
4
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2answers
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Which is better for a home media server: zfs or btrfs or LVM/md? [closed]

I'm looking at building a new home server and would like a flexible filesystem. Both btrfs and zfs are interesting. I want to be able to do soft raid and have flexible solution allowing me to expand ...
4
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1answer
5k views

Can I cache an mdadm raid with an ssd?

I have a 1TB array set up in raid 1 using mdadm on Ubuntu 8, to store mission-critical files. I'd like to speed up read/write, especially for large files by caching to an SSD. Is this possible? Does ...
4
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4answers
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Can I create a 4TB Raid 1+0 volume?

I'm thinking about setting up a NAS based on Ubuntu server, but before I invest the money, I want to make sure what I want to do is possible. What I'm thinking is a 4x2TB Raid 10, so my usable ...
4
votes
1answer
476 views

Can't boot after converting lvm2 root to lvm2 raid1

I have Ubuntu 12.10 (no updates, kernel 3.5.0-17-generic) on first HDD (sda), which uses MBR and was partitioned as "Use whole disk for ubuntu" with LVM2 enabled. Root filesystem is on LVM2 ...
4
votes
3answers
5k views

RAID 1 array not found in server installer

So I'm trying to install the last version of Ubuntu Server 11.10 64bits on my server ( replacing Windows Server 2008 completely ). Since I need more Sata ports, I bought a PCI Sata RAID Controller ...
4
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5answers
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How do I automount a fake raid?

Hardware Asus K8N4-E Deluxe Mobo Sil 3114 fake raid, onboard 2 Seagate 250 gb hd, hosting my /home A backup on a separate hard disk of /home What I have so far I've made the raid using the Sil ...
4
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1answer
2k views

Does 12.04 support the Dell Perc 6i RAID card?

I have a Dell Perc 6i RAID card currently used under Win 2K3 and I am going to transit to Ubuntu Server 12. Since Dell only provides driver for Ubuntu 10 Server yet Dell servers with this RAID card ...
4
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2answers
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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 ...
4
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3answers
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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 ...
4
votes
1answer
4k views

How do I create a RAID5 at installation of Ubuntu 12.10?

For the life of me I cannot find the way to create a RAID 5 set while doing a clean install of ubuntu 12.10. It appears the "Alternate" installation disk either doesn't exist or I am looking in the ...
4
votes
1answer
2k views

GRUB could not find Windows 7 after installing Ubuntu - RAID 0

I just purchased a new computer with two 256 GB SSDs configured in RAID 0. It came pre-installed with Windows 7, but I wanted at least one Linux distribution installed as well. So, I tried ...
4
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3answers
381 views

Why does Grub2 break EVERY time I update my laptop?

I'm running Ubuntu 11.04. I just don't understand it. It doesn't matter if it is a kernel upgrade, or an Adobe Flash update. The next time I restart my computer Grub2 breaks. All I get is a blinking ...
4
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1answer
2k views

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 ...
3
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2answers
3k views

How to install using btrfs in RAID10 mode?

As a test I want to install Ubuntu 11.10 onto a btrfs file system in raid10 mode. However, I have no clue on how I should go about that. I have tried the installer, and then creating the fs in the ...
3
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2answers
14k views

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, ...
3
votes
2answers
4k views

Should swap and RAID-1 mix?

I have a box with a small RAID-1 array being used for swap space. I only did this since I was setting up mirrors for every other partition in the system. Today I read this question and it prompted ...
3
votes
4answers
7k views

What to do about a corrupted ZFS Pool

Have been running a test instance of a NAS using a ZFS as mentioned in Restoring an Ubuntu Server using ZFS RAIDZ for data. This week one of my disks died. Shouldn't be a problem, should it (the ...
3
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2answers
2k views

Is it possible to grow a luks-encrypted external raid5 array?

I'm planing to buy an external raid array (hardware raid5). My intention is to outfit it with 4 disks initially and encrypt it using luks and dm-crypt. My question is: Will I be able to hot swap disks ...
3
votes
2answers
2k views

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 ...
3
votes
1answer
536 views

Is it normal that mdadm has to start from scratch when I restart my computer while it's rebuilding the third disk?

I've installed a RAID5 using mdadm yesterday. Since then it has been rebuilding. I just restarted my computer and it started rebuilding the RAID from scratch. (Had 60% before.) Is this normal or are ...
3
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3answers
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MDADM Superblock Recovery

After a power cycle I found my RAID 5 Array no longer working. I tried various methods to reassemble the array but nothing has worked so far. I believe I need to recreate the superblocks and UUIDs ...
3
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1answer
319 views

Improving virtual Ubuntu hdd performance running on Windows host

I have a Windows 2008 R2 server with: 1 x 80GB SCSI, partitioned: 100MB reserved 79GB NTFS windows 2 x 1TB SCSI HDD running in a hardware RAID 0 striped configuration, partitioned: 7GB RAW (left ...
3
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1answer
393 views

RAID 5 reassemble stating wrong homehost?

So I went from a degraded RAID, to a dissasembled RAID, to now trying to reassemble it. Im getting a weird message when trying to --assemble the RAID. I have 6 drives, so /dev/sd[a-f]1. When trying to ...
3
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2answers
3k views

Installing Ubuntu with Fake RAID 1

I had: Software: Dual boot with Windows XP Ubuntu 10.04 LTS x32 Hardware Fake RAID 1 (mirroring) with 2x1 TB: Partition 1 - Windows Partition 2 - SWAP Partition 3 - / (root) Partition 4 - ...
3
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2answers
679 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 ...
3
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1answer
594 views

Having trouble with HighPoint RAID Drivers on Ubuntu 12.04 LTS

I am building a storage server with the following components: U-NAS NSC-800 Server Chassis ADATA Premier Pro SP600 ASP600S3-32GM-C 2.5" 32 GB SATA III MLC Internal Solid State Drive (SSD) ASUS ...
3
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1answer
4k views

How to install Ubuntu 12.04 server with RAID1?

I have spent the last 4 days or so trying to setup Ubuntu server 12.04.2 with RAID1. I have looked at several different links and tried different configurations and workarounds. So far, I have not ...