The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
0answers
20 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
40 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
30 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
30 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
65 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
46 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
votes
0answers
25 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
62 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
84 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
130 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
43 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
263 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
68 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
votes
0answers
33 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 ...
1
vote
1answer
142 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
128 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
176 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
47 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
268 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
73 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
82 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
203 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 ...
1
vote
1answer
282 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
621 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
62 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
137 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
3k 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
69 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
86 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
48 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
578 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
137 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
2k 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
253 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
699 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
194 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
8k 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
109 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
104 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 ...
5
votes
3answers
896 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
231 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
1k 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
3k 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
377 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 ...