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0answers
7 views

Btrfs distribute files equally across multiple devices

I have a btrfs volume across two devices that has metadata RAID1 and data RAID0. In the event one drive would fail, practically all files above the 64KB default stripe size would be corrupted. As this ...
0
votes
0answers
14 views

Debian 8 sytemd “found device” multiple times

I currently run a Debian 8 system (upgraded from Debian 7) with a software raid 1. Once in a while systemd reloads 3 times in a relatively short period and logs it into syslog. If it reloaded only ...
1
vote
1answer
13 views

grub-install : File descriptor 3 leaked on vgs invocation

I installed Debian Jessie on a LVM in a software RAID 1. To make sure MBR are written on both disks of the RAID 1, I run dpkg-reconfigure grub-pc (as suggested here) and select both disks. I get ...
2
votes
2answers
47 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 ...
3
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3answers
115 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 ...
0
votes
1answer
29 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
58 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 ...
2
votes
1answer
67 views

Centos 7: /dev/md/root instead of /dev/md0

I have in mdadm.conf the following: ARRAY /dev/md/root level=raid1 num-devices=2 UUID=331de03d:8ba39777:3b664baf:36366f33 But here is mdadm.conf example with the following: ARRAY /dev/md0 ...
2
votes
1answer
36 views

How to set up robust RAID 6?

Perhaps I'm going about this all the wrong way, but I am having chronic trouble managing a RAID6 software array in CENTOS7. The system has an internal pair of drives (2x500GB) in RAID1 which has been ...
4
votes
2answers
114 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, ...
0
votes
1answer
137 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
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0answers
30 views

Software raid problem

We have a software raid on our server and we have a problem with disk performances. From time to time disk i/o freezes. During those periods iostat shows that one disk is faster than another. Both ...
2
votes
1answer
98 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
vote
1answer
118 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 ...
1
vote
2answers
202 views

What is the correct way to set up sw RAID1 so either drive boots?

I've set up a non-UEFI CentOS 6.6 "blank" install with /boot and / each in a separate RAID 1 (3 drives/1 spare). I removed one drive, rebooted, and let it sync to the spare. When I saw this was ...
1
vote
1answer
48 views

Rebuild linux raid array?

I'm going to be building a media server soon and I want to know how hard it would be to rebuild an array in the event of an ssd failure. Here's what I'm doing. I'm going to have a 128GB SSD boot drive ...
0
votes
2answers
332 views

Slackware 14.1 software raid kernel panic unable to mount root fs

Trying to install slackware onto a raid 1 on 2 2TB drives. I followed the official readme. I have two drives, sda and sdb. They each have two partitions, one for /(50GB) and one for /home(Rest of ...
0
votes
1answer
96 views

Hot swapping a mirrored disk on a HP UX

I'm trying to do a hot swap on a mirrored lvm. $ vgdisplay -v /dev/vg00 --- Physical volumes --- PV Name /dev/dsk/c2t0d0s2 PV Status unavailable Total PE ...
0
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0answers
37 views

How to recover a partition recreated with gparted

Yesterday I've had the bad idea to try to follow this tutorial : http://fds-team.de/cms/articles/2013-12/use-a-real-windows-7-partition-in-virtualbox-kvm-vmware-player-u.html these are the commands ...
3
votes
1answer
186 views

Unable to check a mdadm RAID1 array, says the file system's read only?

I recently migrated a RAID1 from a CentOS 5 system to a CentOS 6 system and ever since when I attempt to perform a check I get the following: $ echo 'check' > /sys/block/md127/md/sync_action ...
3
votes
1answer
161 views

RAID 5 built using mdadm starts in degraded mode. Is this normal?

I am setting up a new set of drives on a CentOS 7 installation (10x1TB), however am seeing something annoying during the build process. When I attempt to build the array, it is immediately recognised ...
1
vote
0answers
190 views

Configuring RAID on a running Ubuntu 14.04 Server

First please bare with me as while I'm no total newbie to Linux this is my first venture into running and administering a webserver. I'm currently renting a dedicated server which I thought was ...
2
votes
2answers
52 views

Recovering mismatched sectors in a RAID array

I recently got an automated email saying "WARNING: mismatch_cnt is not 0 on /dev/md3". I'm running a software RAID5 array using mdadm on CentOS 6.6 When Googling the message I found this:- The ...
1
vote
2answers
336 views

Create a Software RAID 1 on a Linux server (openSUSE server)

I have a server with openSUSE 13.1 on a single HDD (500 GB WD). The server has information on it and its working properly. Can i create a software RAID1 inserting a second 500 GB WD HDD? How can this ...
2
votes
2answers
83 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 ...
1
vote
3answers
93 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] ...
1
vote
2answers
225 views

Missing mdadm raid5 array reassembles as raid0 after powerout

I had RAID5 array of three disks with no spares. There was a power out, and on reboot, the array failed to come back up. In fact, it the /dev/md127 device disappeared entirely, and was replaced by an ...
2
votes
1answer
347 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 ...
0
votes
3answers
831 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 ...
3
votes
1answer
2k 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 ...
2
votes
1answer
70 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
vote
1answer
147 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 ...
7
votes
2answers
4k 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 ...
0
votes
1answer
73 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 ...
1
vote
0answers
23 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 ...
0
votes
0answers
89 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 ...
2
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0answers
51 views

MD soft-raid to replace fake raid: How to get rid of old metadata?

I had a system running with fake RAID (Intel controller, imsm), which had some problems. Now I'm switching to the regular MD soft-RAID - I created a RAID 1 on /dev/sda1 and /dev/sdb1. Seems to work ...
1
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0answers
620 views

Help with lost software RAID5 on CentOS 6.5

I've been searching for hours and giving up / too scared to delete all my data. I have a file server running CentOS 6.5 which has 4 WD RED 2TB drives (all > 1 year old) in software raid 5 with mdadm, ...
1
vote
1answer
155 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
vote
1answer
3k 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: ...
2
votes
1answer
301 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] ...
3
votes
1answer
2k views

Can't mount RAID after upgrade

I just upgraded my box to 14.04 and on bootup I got a message, that my RAID devices can't be mounted automatically so I chose to skip it and work through it after boot time. Now booted up, A mount -a ...
2
votes
1answer
849 views

mdadm : difference in metadata versions

Can anyone tell me the difference between the different metadata versions for mdadm? When I try the command mdadm --examine /dev/sda1, I can't seem to find "preferred superblocks" on version 1.2. ...
0
votes
2answers
210 views

Two arrays have slightly different array size with same size disks/partitions, why?

I created a software RAID 5 array one year ago using mdadm v3.2.x which shipped from CentOS 6.3, after few months, I moved/assembled the array to/in Fedora 19 (now Fedora 20). It had three 3TB disks ...
4
votes
1answer
9k views

How to setup a RAID system using USB sticks as storage media

I want to create an inexpensive self-hosted private git server with redundant storage. To that end I have bought a Raspberry Pi and configured both git and ssh on the Pi. I can access the Pi both from ...
2
votes
1answer
121 views

Linux software-RAID and bootloader

How is it ensured that Linux software-RAID superblock(for example version 1.2) can be created at 4KiB from the beginning of the drive? According to manual of mdadm it is. I mean isn't there a hazard ...
3
votes
1answer
56 views

understanding the “chunk size” in context of RAID

Am I correct that chunk size in context of RAID is essentially the same thing as cluster in file-system context? In other words, chunk size is the smallest unit of data which can be written to a ...
1
vote
1answer
110 views

understanding Linux software-RAID superblock

According to mdadm manual, --zero-superblock option will overwrite the superblock with zeros. As I understand, superblock is a 256 byte block on HDD/SSD describing the RAID level used, name of the ...
3
votes
1answer
1k views

Software RAID 10 + LVM on mixed drives, sector alignment?

I have 4 2.5" 7.2k drives lying about and I'd like to build some RAID arrays for a bit of VM storage on my KVM lab box. There are 2x 320GB drives and 2x 500GB drives. I'm looking to create a RAID 10 ...
2
votes
1answer
2k views

mdadm - RAID5 array size vs. actual disk size mismatch

I have 4x 3TB WD RED disks that are in mdadm RAID5, which should total an array size of 9TB usable space, however I only have 6TB. I have confirmed all disks are in the array, the only strange thing ...