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, ...
26
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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
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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: ...
12
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7answers
23k 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 ...
11
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5answers
31k views

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 - ...
10
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4answers
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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 ...
10
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1answer
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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 ...
9
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2answers
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How to Install Ubuntu 14.04 with RAID 1 using desktop installer?

Many people claim that it is impossible to install Ubuntu onto RAID 1 with the Desktop CD. Is this really true? If not, how can it be done?
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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 ...
8
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1answer
17k 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 ...
8
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1answer
33k 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 ...
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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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2answers
16k views

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 ...
7
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4answers
14k 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
7k views

How to implement RAID 1?

How to set up RAID 1 [software, hardware or fake] on Ubuntu 12.04 desktop?
7
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2answers
6k 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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2answers
9k 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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1answer
16k 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 ...
6
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5answers
4k views

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 ...
6
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2answers
3k 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
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How to re-add accidentally removed hard drive in RAID5

I have a NAS on Ubuntu Server with 4 2TB hard drives in RAID 5. A couple of weeks ago, one of the hard drives died, but my RAID was working, although degraded. Luckily it was still under warranty and ...
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4answers
844 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 ...
6
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2answers
163 views

OS - Does not Show 100% HDD Capacity

I am from Dell Technical Support -- One of our customers has a Dell System Model T5610 and has installed 2-256GB SSD HDD and 2- 4TB HDD and Configured RAID-0 of 2 Arrays on Intel Based Chipset ...
5
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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 ...
5
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2answers
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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 ...
5
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3answers
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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
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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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4answers
2k views

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 ...
5
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2answers
15k 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
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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 ...
5
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1answer
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How To Install Ubuntu 14.04 on HP Dynamic Smart Array b120i logical drive

I've got some problems when trying to install ubuntu on hp proliant dl 160 gen8. I've got 3 logical drives in dynamic smart array controller, and on installation screen I see only physical drives. How ...
4
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3answers
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How to install Ubuntu server with UEFI and RAID1 + LVM

I used to install my servers with LVM over software RAID1, and grub install on the MBR of both drives. Now I have an UEFI server, and the compatibility (BIOS) mode does not seem to work. So I went ...
4
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2answers
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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, ...
4
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1answer
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Dual-Boot Ubuntu 14.04 and Windows 7 on FakeRAID Installation error - question marks “????…”

I am trying to install Ubuntu 14.04 on FakeRAID along Win7. Win 7 has been already installed, and dmraid is running. During the installation I choose to manually partition, this is the structure: ...
4
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1answer
6k 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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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 ...
4
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2answers
950 views

How can I use Kernel 3.19 in 14.04 now?

So I'm rebuilding my storage server. For stability, I want to use Ubuntu server 14.04 LTS as the OS. However, I'm planning to use Btrfs with RAID 5, and this has been greatly improved in kernel 3.19. ...
4
votes
1answer
740 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
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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 ...
4
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3answers
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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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1answer
7k views

Disks constantly spinning no matter what I do (jbd2). I'm on the brink of insanity

My disks have been spinning for months. It started with Ubuntu 11.10, and continues with 12.04. I can't figure out how to stop it. I've looked at various folks suggestions online about ext4 commit ...
4
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1answer
2k views

Resizing partitions on a RAID 0 Array by command line

Oh boy this is a qustion and a half. Simply put when i set up the server it wasn't intended to be used for what it is now, and root (/) has run out of diskspace, while /home has tonnes of the stuff ...
4
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1answer
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SSD + TRIM + ext4 OK. What about LVM and RAID?

I've read that SSD TRIM is now supported in the recent kernels with ext4 too (see How to enable TRIM? ). Is it OK/safe to enable TRIM when having a) LVM b) RAID1+LVM? Thanks!
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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
11k views

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
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1answer
5k 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
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1answer
3k views

Unable to Install GRUB in /dev/sda on raid drives

I'm trying to install 12.04LTS on a server but keep running into the unable to install grub error like so "Unable to Install GRUB in /dev/sda". The drives are in raid1 and I'm using fakeraid on a ...
4
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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
390 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 ...