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1
vote
2answers
12 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 ...
1
vote
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 ...
1
vote
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] ...
1
vote
1answer
42 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 ...
0
votes
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 ...
0
votes
3answers
117 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
votes
1answer
331 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
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
vote
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
votes
0answers
362 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
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 ...
1
vote
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 ...
0
votes
0answers
61 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
votes
0answers
30 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
vote
0answers
345 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
74 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 ...
0
votes
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: ...
2
votes
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] ...
0
votes
0answers
38 views

Ubuntu raid dirty degraded

I have Linux version 3.5.0-17-generic (buildd@allspice) (gcc version 4.7.2 (Ubuntu/Linaro 4.7.2-2ubuntu1) ) #28-Ubuntu SMP Tue Oct 9 19:31:23 UTC 2012 (per /proc/version). There are two raid arrays ...
3
votes
1answer
795 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 ...
1
vote
1answer
215 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
149 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 ...
2
votes
1answer
4k 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
65 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
50 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
79 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 ...
2
votes
1answer
737 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
1k 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 ...
5
votes
3answers
452 views

Poor IO due to LUKS/Software RAID/LVM ordering?

I'm trying to determine if I should re-setup my RAID array due to poor IO performance. First off, the system: i7 920 4 4TB WD 5400 Green drives CentOS 6.3 host Secondly, the disk setup: ...
1
vote
1answer
190 views

Removing failed disk from raid 1

my server (Debian Wheezy) has a failed disk. I have sda and sdb and according to the support of my hoster, sdb needs a replacement. I send them this information with the mdstat: ...
2
votes
1answer
926 views

Mount an existing RAID 1 Logical Volume after OS upgrade

I just upgraded from Ubuntu 10.04 to Mint 16. The installer did not detect my existing RAID 1 array, and I can't access it anymore. My drives are: SDA - First RAID Disk SDB - Second RAID Disk SDC - ...
2
votes
2answers
2k views

Best way to create RAID on an existing system drive

I want to add another disk as RAID 1 to test my database performance. I am trying to not re-do the whole system, is it possible? Currently I have a single 1TB HDD with one 100GB system partition (and ...
6
votes
1answer
289 views

md raid1 ext3 and 4k sectors slow with directory operations

I recently moved from a hardware RAID1 enclosure to using two eSATA drives with md. Everything seems to be working fine, except for the fact that directory traversals/listings sometimes crawl (on the ...
2
votes
1answer
58 views

Linux installation in RAID

I am a fairly new systems administrator and I have to configure the RAID on a Linux machine. From my understanding so far, RAID is an array of multiple disks. I have some questions though. Question ...
4
votes
2answers
722 views

How does Linux md-RAID handle disk read errors?

There are 2 cases: the read command times out at kernel level (30 seconds by default), the drive reports its unability to read a given sector before the kernel lose patience (the case I'm ...
3
votes
1answer
376 views

mdadm; previously working; after “failure”, cannot join array due to disk size

Abstract I had a functional Raid 5 array, I rebooted the box, and then mdadm couldn't re-assamble one part. Seeing that it was only one part, I thought it would be easy to just re-sync. But that ...
2
votes
1answer
475 views

Kernel failure with software RAID-1 due to single drive read errors

I am running Fedora 19 (kernel 3.11.3-201.fc19.x86_64) with a software RAID-1 (mdadm) setup on two identical Seagate 1GB drives: # cat /proc/mdstat Personalities : [raid1] md1 : active raid1 ...
1
vote
1answer
287 views

Ubuntu Server - OS on single HDD, file server on software RAID 1

I run a Windows Server 2008 machine. It is used as a file server (File Services feature), in addition to local shares I use CrushFTP for SFTP and HTTP access to my files. I would like to convert to ...
5
votes
4answers
2k views

Monitor disk health using smartd (in smartmontools) on a high availability software RAID 1 server

I have a server with three identical SATA/600 3TB drives: /dev/sda, /dev/sdb, /dev/sdc. The drives are partitioned, using GPT with three partitions each: 1 MB: Reserved partition for boot loader 1 ...
3
votes
1answer
330 views

Can zfs resilvering destroy data with misreported device failures?

I have had a situation where I am moving data into a new zfs raidz pool with four devices, some of them virtual to facilitate the migration. The system completely hung in the middle of a device ...
4
votes
2answers
3k views

What does mdadm's “spare” number mean?

I created a mdadm-based RAID 5 from six hard drives using the following command: # mdadm --create /dev/md0 --level=5 --raid-devices=5 \ /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 \ ...
2
votes
2answers
344 views

Can I create a 2 TB RAID-1 array out of one 2 TB disk and two 1 TB disks while preserving 1 TB of data?

I currently have 1 TB of data on a RAID-1 mdadm array. This array consists of one 1 TB disk and a 1 TB partition on a 2 TB disk. I have now bought a second 1 TB disk, and I would like to use this to ...
4
votes
1answer
148 views

Reusing older raid discs

I have a software RAID5 array (Linux md) on 4 disks; the OS is OpenSUSE 12.3. Recently I replaced a disc with a larger one (fail disc, remove it, add new disc). The capacity of the array has not yet ...
3
votes
1answer
325 views

What are potential consequences of going nuts with sparse file based vdevs for a LVM to ZFS migration?

I've been playing around with ZFS having finally accepted that it's mature enough I shouldn't get burned. Now to migrate the home NAS box which is currently an LVM JBOD set up that's quite full, but ...
1
vote
2answers
963 views

erased md0, md1 and can't recreate them

I previously had a working RAID 1 array. I think as a result of running grub-install /dev/sdb and grub-install /dev/sdc I somehow wiped my computer of md0 and md1. I need to set them up again. When ...
1
vote
2answers
179 views

Raid5 Device Has Less Space Than Expected

I have 3 3TB drives, and have raid5ed them together. I would expect to get a resulting device around 6TB. The command I used: mdadm --create md0 --level=5 --raid-devices=3 /dev/sda1 /dev/sdb1 ...
2
votes
0answers
165 views

What changed between kernels 3.7 and 3.9 that affects LVM/RAID root file systems?

I'm trying to fix a (very messy) system that the user hosed by running a kernel upgrade from 3.7.10 to 3.9.6. the root file system is on an LVM volume on top of a software RAID array. The boot manager ...
4
votes
1answer
3k views

No /etc/mdadm.conf in centos 6

I have installed centos 6 and setup a new RAID array with two disks. every thing is ok and I have partitioned the array but I don't see any /etc/mdadm.conf or /etc/mdadm/mdadm.conf files. I have ...
4
votes
3answers
2k views

How to safely replace a not-yet-failed disk in a Linux RAID5 array?

I have a software RAID5 array (Linux md) on 4 disks. I would like to replace one of the disks with a new one, without putting the array in a degraded state, and if possible, online. How would that ...
4
votes
3answers
3k views

lost superblock in md raid

Issue on Red Hat Linux 5. Due to some miscommunication two LUNs in our environment were enlarged from 1.2 TB to 1.7 TB. Now, after a reboot, mdadm does not find the superblocks to build the array ...