Tagged Questions

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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2answers
16 views

Raid 5 not starting

I had a raid 5 with 3 disks in my old computer, but the motherboard died. I put all the disks in a New computer, but the raid doesn't want the start anymore. When booting the pc, i can see all ...
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1answer
31 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 ...
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0answers
12 views

Mdadm not adding all disks to raid

A couple of years ago, I installed a raid 5 with mdadm on a fedora box. The old hardware died recently, and I have put the boot disk in a newer desktop pc, and added the thee raid disks via usb. So ...
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0answers
51 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 ...
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3answers
32 views

Software RAID10 setup writes small files extremely slowly, is this normal?

I have a software RAID-10 setup on Linux 3.16.6-203.fc20.x86_64, with 1.2 metadata and the default chunk size (512K): $ cat /proc/mdstat md0 : active raid10 sdc1[4] sdb1[0] sdd1[2] sde1[3] ...
3
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1answer
99 views

Grub fails to install - Debian Wheezy with mdadm RAID1 and GPT partition table

I've been trying all day to get my new Wheezy install completed but it fail to install Grub every time. I'm using x64 netinstall iso. Here is my partition table: Model: ATA ST3000DM001-1CH1 (scsi) ...
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1answer
15 views

mdadm - What's the difference between --detail --scan and --examine --scan?

From man mdadm: -E, --examine Print contents of the metadata stored on the named device(s). Note the contrast between --examine and --detail. --examine applies to devices which are ...
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0answers
90 views

btrfs balance fails due to enospc error

[taken over from stackoverflow since I figured that was probably the wrong place] I am currently testing btrfs as a possible replacement for my NAS running ZFS. I created 4 devices, 20GB each, and ...
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0answers
21 views

Files and Directories Dissappearing from Software Raid on Power Failure

I have a home samba file "server" (a raspberry pi) with two hard drives in a software raid 1, which have proven less reliable than any of my non-raid disks. I know there is a chance for data ...
1
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2answers
26 views

Spanning RAID over SSD and Mechanical HD

Currently I have my root (/) directory on my ssd, and my home directory on my mechanical drive. Wanting to utilize more of the ssd and hopefully get a speed benefit, I was considering spanning across ...
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0answers
16 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 ...
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2answers
21 views

Whose responsibility is to divide data into PEs or chunks?

When we create LVMs or the RAID partitions, the data we save in the parition is divided into PEs or the chunks respectively instead of the conventional blocks of ext3 or ext4. My doubt is whose ...
0
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1answer
21 views

A SparesMissing event had been detected on md device /dev/md0

I'm getting the following mail every day on a server: This is an automatically generated mail message from mdadm running on <host> A SparesMissing event had been detected on md device ...
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0answers
22 views

server can't read newly installed centos 6.1

I have a server that has 12TB and I used RAID 1+0(RAID 10) so my logical drive in the server is now 6TB + (6TB Mirror) when I install the CentOS v.6.1 in the server, the installation has no problem at ...
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3answers
36 views

Linux SW RAID and physical volumes

In each guide about software RAID in Linux, I could find online I see that people usually create/assemble RAID devices using partitions, like: mdadm --create --verbose /dev/md0 --level=5 ...
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3answers
118 views

How to combine multiple HDDs into one big HDD in Linux?

I'm very new to Linux, being mainly a Windows 7 user, so I may not understand Linux-specific commands without explanation. I've decided to build a NAS running some form of Linux (probably FreeBSD or ...
2
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1answer
337 views

How to install Debian Jessie properly onto multiple devices with BTRFS in mode RAID 1?

As a short introduction I'm going to tell you, what kind of setup I have and what I want to achieve. After that I try to explain my problem. Since this is my first question on U&L I have to ...
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0answers
237 views

How to make Intel fake RAID 0 volume appear on boot with Ubuntu 14.04 in a multi-boot environment?

I have a computer with a Gigabyte GA-Z97N-Gaming 5 mainboard, a 256 GB drive for booting and two 3 TB drives meant to use in a RAID 0 setup with both ext4 and NTFS partitions. We are planning running ...
0
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1answer
19 views

Is there anyway to get the hardware information on a hardware RAID 1 while inside of the OS?

Is there any way to see the information on a hardware raid while still being in the OS? Things to note: I am remotely connected to this machine (so I cannot physically see the information of both ...
0
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1answer
42 views

If MBR is broken, how to fix on RAID + LUKS encryption?

Problem: After HDD failure in a Software-Raid Mirror Debian does not boot. Only black screen with blinking _ Debian Setup: Within the raid I have a complete system encryption with luks. I am not ...
2
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1answer
45 views

Raid 5 rebuild with wrong stripe size & no failed disks - is data lost?

I'm curious if there are hidden complexities to RAID5 and RAID5 rebuilds. My understanding is that (in a 3 disk array) a rebuild would just directly compute the parity of disks 1 & 2 and write ...
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0answers
329 views

What are the steps needed to get Redhat/Centos 7 to boot from an mdadm RAID?

I've spent a day on this. Figured it was time to ask. In the end I couldn't get around "Bad magic number in super-block ..." On an average install, my sda exits setup as an EFI. I'm cool with that ...
0
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1answer
76 views

XFS on Volume Group or Mdadm Raid 0

Im starting to use XFS because I want to create a highly parallel disk array and experimenting on just 2 drives for now. I had thought that if I used a logical volume group to join two physical ...
2
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1answer
75 views

Why is so much of my new ext4 filesystem already marked as used?

I have just created a new raid 5 array using 3 4TB drives (aiming for 8TB of space) on an ubuntu system. While I had a few issues getting started, I believe I have set it up correctly and I have ...
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0answers
199 views

How to write to RAID 1 disks on Raspberry PI

I'm using Arch Linux on my Raspberry Pi, though I'm not sure that's relevant. I followed this tutorial to set up a RAID 1 array with 2 USB HDs. I then mounted the array (md0) in /media. What I ...
2
votes
1answer
35 views

Moving software RAID 1 to Linux

I'm using a RAID 1 (mirrored pair) configuration in my Media Center/ NAS system. Currently it's running Windows 8 (yeah, big mistake I know) and I'm regretting it (did it for the games, not worth it). ...
1
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1answer
94 views

chroot into system

Update : Following the advies of slm, I could destroy the RST raid 0 and create a new raid0 using mdadm using the webpage he gave me. I could start the installation but at the step where grub is ...
3
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0answers
368 views

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 ...
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0answers
31 views

Discovering possible RAID configuration of a bunch of disks

I have a stack of 8 disks which were at one point all inside of one host. That host no longer exists, but it's been requested that I retrieve data from these disks. No one can tell me anything about ...
1
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1answer
48 views

Clone installed system by using the hardware RAID 0+1 synchronization

Alright, following setup: 2 identical machines (DELL Power Edge T320) with a hardware raid. one machine is running for a while now, one machine hasn't even been set up at all The running machine ...
0
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1answer
45 views

RAID Level 5 versus Level 1

Is it slower to write one block in RAID Level 5 with 5 disks than RAID 1 with two disks (mirroring only)? I think No since with Level 5 you are writing the data and the parity (two writes). With Level ...
3
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1answer
87 views

Recover data from raid 1 when both drives are faulty

I had a RAID 1 on my server, and apparently both of hard drives have failed at the same time. Server support did a quick check to confirm that HDDTEST-W1F21M6K ERROR Finished (Selftest, Device: ...
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2answers
60 views

mdadm metadata: should i take precautions to prevent superblock overwrite?

Situation: I'm creating a new RAID1 array using mdadm. I won't be using additional layers, such as LVM or dm-crypt. I've noticed that metadata version 1.2 is now the default. I understand it's the ...
0
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1answer
2k views

mdadm raid doesn't mount

I have a raid array defined in /etc/mdadm.conf like this: ARRAY /dev/md0 devices=/dev/sdb6,/dev/sdc6 ARRAY /dev/md1 devices=/dev/sdb7,/dev/sdc7 but when I try to mount them, I get this: # mount ...
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1answer
39 views

Recovering a (not yet created) RAID5 with URE (Unrecoverable read errors)

I wan't to create a RAID5 array at home, the OS is Linux (Kernel 3.15.7) and the array will be created with mdadm. I wan't to create the array with eigth or ten 1TB discs. Let's assume a single drive ...
2
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3answers
136 views

Reassemble mdadm-raid5

A friend of mine has a mdadm-raid5 with 9 disks which does not reassemble anymore. After having a look at the syslog I found that the disk sdi was kicked from the array: Jul 6 08:43:25 nasty ...
3
votes
1answer
103 views

RAID-1 mirror has become a single hard disk

I have an HP N40L microserver, with 2 identical drives, I used the system to hardware-RAID them as a mirror. I then installed mint on the system about a year ago. This has been running perfectly, ...
2
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0answers
52 views

how to reverse the effect of sgdisk -R=/dev/sdb /dev/sda?

I accidentally used sgdisk -R=/dev/sdb /dev/sda instead of sgdisk -R=/dev/sda /dev/sdb after replacing a broken drive in a raid. Can I recover from this or is all data lost now?
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0answers
22 views

Is it reliable to assemble md from two machines at the same time

Say we have the same disks accessible from two machines. I want to do assembling md from two machines. Is it possible/reliable ? The disks are connected through SAS. All I need to have is reliable ...
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0answers
62 views

Moved Raid from NAS box to PC running Ubuntu hdparm shows drives frozen

So I had a RAID5 setup in a Partriot S4 Javelin (a NAS box). I'm now migrating it to a proper server running Ubuntu 14.04. NOTE: There are 4 drives. All the drives show up in Ubuntu. Two show ...
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0answers
12 views

How to increase an FS using a LiveCD - that has SW RAID+LVM

If we have an older OS and can only increase the FS if we umount the FS because it is the ex.: /usr - then we have to use a LiveCD. The /usr is in the rootvg (LVM) that is on a SW raid Q: What are ...
2
votes
2answers
55 views

mdadm - exclude drive from monitor

I have created a RAID 1 array with a single drive (in order to add a second drive later). # mdadm --create /dev/md5 --level=1 --raid-devices=2 /dev/sdc1 missing But, I execute /sbin/mdadm --monitor ...
1
vote
1answer
75 views

mixed raid types

I am about to reinitialise my (SW) raid array. Previously the array was raid5 with 4 disks. I've removed one disk in order to install a new additional (larger) drive. What I'd ideally like to do is ...
1
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1answer
790 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 ...
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1answer
70 views

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: ...
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0answers
80 views

automatic disconnection of RAID array

A RAID array connected to my system (Debian 7) via USB frequently disconnects itself for no apparent reason. Upon initial connection to the system, the device is detected, and the array can be ...
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0answers
51 views

Raid 1 or just mirror SATA and USB Harddisk

I think about getting a Cubieboard, and to set up a Linux with OwnCloud. The board has a SATA and two USB Ports. I would like to store the main data on the SATA-HD and use a USB-HD as backup. How ...
3
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0answers
59 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 ...
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0answers
48 views

Converting RAID partitions to LVM

I have a 3TB HDD. of type RAID 5. I want to convert it to LVM. How can I do this without data loss and without needing for installing the OS again? $ df -h Filesystem Size Used Avail Use% ...
2
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1answer
100 views

How do I know if software raid is running or setup correctly

This is what I pulled: mdadm --monitor --scan -f --pid-file=/var/run/mdadm/mdadm.pid cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sda1[0] sdb1[1] 262080 blocks super 1.0 [2/2] ...