RAID solution handled by the operating system.

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Single drive LVM to RAID6 LVM

I cloned my entire LVM volume group from a single drive to a RAID5 array with 3 disks. The VG is formed by these logical volumes: root swap home ... and other volumes of some XEN virtual machines. ...
2
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1answer
215 views

How do I find out which disk in a multi-disk mdadm RAID1 triggered a rebuild?

I'm using mdadm for several RAID1 mirrors. md7 is an N-way mirror consisting of 3 spinning disks (all flagged write-mostly) and an SSD: md7 : active raid1 sdd1[0] sde5[3](W) sdf5[4](W) sdc1[1](W) ...
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2answers
194 views

Linux software RAID - partition first?

I have two identical drives that I intend to mirror in in the interest of data safety. These are data-only drives, not a primary OS drive. In such a system, is it better to create single partition ...
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2answers
494 views

iSCSI Distributed RAID?

Thinking about setting-up as distributed RAID array over iSCSI. Has anyone else tried this, if so what was your experience. To be more specific I am thinking of a couple of CentOS servers each with ...
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0answers
38 views

Software Raid mounts random partition

I have mounted Ubuntu server 12 on 2 drives with software raid. I have raid 1 on 4 partitions and raid 0 on swap. Every time I reboot the system now a different partition from the 2 appears as active ...
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2answers
442 views

Linux software RAID6: rebuild slow

I am trying to find the bottleneck in the rebuilding of a software raid6. ## Pause rebuilding when measuring raw I/O performance # echo 1 > /proc/sys/dev/raid/speed_limit_min # echo 1 > ...
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1answer
342 views

Raid 10 - Very slow [closed]

I have Software Raid 10 setup, it has been working great a few months. When I did a quick HD speed test: dd if=/dev/zero of=test bs=64k count=16k conv=fdatasync It is taking forever and I had to ...
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226 views

Reusing slot numbers in Linux software RAID arrays

When a hard disk drive in one of my Linux machines failed, I took the opportunity to migrate from RAID5 to a 6-disk software RAID6 array. At the time of the migration I did not have all 6 drives - ...
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2answers
602 views

Linking FreeNAS Boxes

I have two different FreeNAS boxes that are being used for storage. It is possible to link them in a manner that the linked connection can be presented as a single storage destination for clients? ...
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1answer
888 views

mdadm+zfs vs mdadm+lvm

This may be a naive question since I'm new to this and I cannot find any results about mdadm+zfs, but after some testing it seems it might work: The use case is a server with RAID6 for some data that ...
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1answer
743 views

Linux software RAID6: 3 drives offline - how to force online?

This is similar to 3 drives fell out of Raid6 mdadm - rebuilding? except that it is not due to a failing cable. Instead the 3rd drive fell offline during rebuild of another drive. The drive failed ...
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3answers
2k views

Create mirror software raid with bad blocks hdd. How to check data integrity?

There is error in System event log like this one: "The device, \Device\Harddisk1\DR1, has a bad block." Because of above I created Raid 1 on this disk and other one. I'm using Windows Server 2008 R2 ...
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2answers
371 views

From which plex am I booted from on raid?

I have a server with mirrored boot volume. It is software raid 1 in Windows Server 2008 R2. I do not have physical access to the server. I am looking for a way to check which disk is a boot drive. I ...
3
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2answers
573 views

Linux Software RAID1 Rebuild Completes, but after reboot, its degraded again

I have been beating my head with an issue here, and I'm now turning to the internet for help. I have a system running Mandrake Linux, with the following configuration: /dev/hda - This is a IDE ...
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2answers
398 views

How to Detect Hard Disk Failure

I have a software RAID 1 setup in my CentOS 6.2 and set to be bootable in any of the HDDs in case one of them fails. Questions: How can I recognize if one of the HDDs fail? or early signs of ...
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2answers
3k views

Can't boot after Disk 0 of software raid is replaced

On a windows 2008 R2, which was on a mirrored software raid, Disk 0 has failed. After I replaced it with an alternate drive (can not find the same capacity and model) - the server isn't booting. ...
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2answers
1k views

How to know which disk has failed on a Mirrored Raid? marked as DR0

Our 2ndry DC, which is on a W2K8R2 Mirrored software raid has lost it's sync, and disk management displays the failed redundancy error How do I know which of the disks has failed? (beside to try ...
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1answer
479 views

Controlling mdadm faulty disk rebuild order in RAID 10 array

I have a Linux mdadm RAID 10 array comprising of 6 (SATA) disks configured with n2 copies. While pulling out one disk, another one in another mirror pair failed. Leaving me with: $ cat /proc/mdstat ...
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1answer
84 views

HDrecover on soft raid arrays

I recently used hdrecover to repair a disk and it successfully repaired three bad sectors. How does hdrepair function on raid arrays, is it likely to break the array by repairing sectors?
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2answers
468 views

Risky to have RAID5 with 3x3TB drives? What alternatives should I be considering?

A drive dropped out of my raid 5 array yesterday. It looks like the reason was due to a bad controller so I switched it out and attempted to re-add the drive but mdadm claimed it couldn't do it. So I ...
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1answer
118 views

Converting software RAID1 to RAID10 for /boot

Array info: /dev/md0 -> /dev/sda1 and /dev/sdb1 /dev/md2 -> /dev/sda2 and /dev/sdb2 Partition info: /boot -> /dev/md0 / -> /dev/md1 I have two drives that are setup as RAID1 using software RAID ...
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1answer
1k views

Cannot reactivate RAID-5 volume: The size of the plex member is invalid

We had a 3-drive Windows Server 2008 R2 RAID-5 fail (operating in redundancy mode): WDC 1 TB WDC 1 TB WDC 1 TB We removed the failed hard drive, and put a WDC 1 TB drive (that we had standing by) ...
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1answer
1k views

Linux Software RAID: How to fsck on hard drive?

We have a Linux server running with Software RAID1. We see some issues in /var/log/messages like: unreadable sector. I want to perform a complete fsck on the drive to get some more information, but a ...
3
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1answer
311 views

mdadm kernel log messages explained

Welcome. I try to recover from linux software raid failure. I am in a process of recreating the superblocks based on a syslog from the system when it was healthy. The log speaks about 2 md devices, ...
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1answer
641 views

What parameters to mdadm, to re-create md device with payload starting at 0x22000 position on backing storage?

I try to recover from mdadm raid disaster, which happened when moving from ubuntu server 10.04 to 12.04. I know the correct order of devices from dmesg log, but given this information, I still cannot ...
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1answer
68 views

How many really distinct permutations of volumes are in mdadm raid5 degraded array?

I'm attempting to recover from a failure of my raid volume after upgrade from ubuntu 10.04 to 12.04. I've tried re-creating the array in any combination of 5 elementary volumes with one replaced ...
5
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1answer
884 views

What effect does RAID stripe size have on read-ahead settings?

I'm trying to figure out the correct read-ahead values to set on a RAID10 array, and I'm wondering if the RAID stripe size should factor into my considerations. I've heard conflicting information ...
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1answer
89 views

Linux Software RAID 1 issue

I recently had a HDD failure on a SW RAID1 system (Debian 6.0) and what happened was that the active HDD looked like it had some badblocks which somehow propagated to the HDD that was still OK but it ...
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1answer
7k views

KVM guest io is much slower than host io: is that normal?

I have a Qemu-KVM host system setup on CentOS 6.3. Four 1TB SATA HDDs working in Software RAID10. Guest CentOS 6.3 is installed on separate LVM. People say that they see guest performance almost equal ...
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0answers
119 views

grub2 failing to detect md0 for /

I recently set up a raid 1 array. Both / and /boot are on md0 (sda, sdb). everything was working when it was in degraded mode before I synced the two disks together. It was booting from grub2 on ...
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1answer
136 views

Software raid 0 with six disks performance

I have some problems with disk performance. I have 6 x WD 500Gb RE4 disks. Each disk gives 135Mb/sec throughput. All measurements are made with hdparm with options "-tT" (I know that it is just ...
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1answer
895 views

Linux software RAID60: Can I have global hot spare?

As far as I can see Linux has RAID6 and RAID0, but not RAID60. So RAID60 is emulated by creating RAID0 on top of some RAID6s. It is possible to add a hot spare to each of the RAID6s, but is it ...
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1answer
4k views

Why has ESXi 5.0 not used the software RAID configuration on my test server?

I've got a test server which was running WS 2008 Enterprise on the bare metal. It was correctly using the software RAID 1 configuration (2x250 GB disks which appeared as one disk), setup on the Dell ...
0
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1answer
453 views

Ubuntu server boot degraded raid

I've installed Ubuntu 12.04.1 in a new server and set up the 4 hard drives with 3 RAID 1 devices, the configuration is such that the first two drives have md0 (swap space) and md1 (/) with the third ...
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1answer
115 views

using mdadm, can I add a mirror raid over network for backup purposes?

I have a remote live filesystem I want to make a snapshot of. Using mondo it could work but it slows down the system too much. Using dump/restore could work too but I don't seem to get file ...
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2answers
314 views

Ubuntu 12.04 Server Software RAID1 - Faulty Spare - Smart Output Passed - Confused

I think I'm having an issue with one of the hard drives on my array and I'm just trying to troubleshoot what's happening. Its saying Faulty Spare and then after reboot it just says removed: ...
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3answers
262 views

Analysing Disk IO Traffic

I am running a web server (Ubuntu 11.04) that exhibits unexpected high write traffic. When the server is not supposed to write at all, the amount of write traffic is comparable to the read traffic. ...
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1answer
692 views

mdadm and blkid give different uuid

We recently replaced a hard disk in a server and reinstalled the operating system (Centos 6) The raid rebuilds itself every boot; /dev/md2 is losing a disk each time apparently. Always the same ...
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4answers
406 views

OS or Onboard software RAID?

I plan on installing Debian 6 on my server build with a E3-1270, 16GB DDR3, and 2x120GB SATA3 SSDs. But this has me wondering, should I use Intel's built-in, on-board software RAID or the OSs'? ...
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2answers
708 views

RAID disk failure - Replace disk or whole array?

I have a 5 disk Raid5 array of Western Digital Green (WD10EADS) 1TB. Raid5 is via Windows Server (software raid). One disk has failed, and it looks as though I can't get the same model replacement. ...
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2answers
5k views

Readahead Settings for LVM, Device-Mapper, Software Raid and Block Devices - what wins?

I've been trying to find a straight answer on this one, and it has proved elusive. This question and its answer is close, but does not really give me the specifics I would like. Let's start with ...
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4answers
2k views

Is it necessary to have RAID in a virtual machine?

I have a Windows 2008 Enterprise on RAID 10 running Active Directory, Hosted Exchange, and a web server on HyperV VMs. Do I need a virtual RAID for Exchange? If so, why? Edit: thanks everyone for the ...
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1answer
306 views

Is there a way to prevent a SW RAID 1 from degrading?

I have a number of Debian servers in a datacenter and from time to time I notice that the software RAID 1 was degraded. While the re-sync process starts automatically and I don't lose any data I find ...
0
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1answer
307 views

How do I recover from boot error when my root is on RAID and LVM? [closed]

When a (Archlinux) system that has its root on RAID and LVM is misconfigured and does not boot, what steps are needed to recover it?
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2answers
761 views

Determining the software RAID configuration on an Ubuntu server

I have an Ubuntu box which was installed by an admin who is not with me now. I have no information on how he configured the RAID and neither no experience on setting up a software RAID on Linux ...
4
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1answer
366 views

3 drives fell out of Raid6 mdadm - rebuilding?

i had an mdadm raid6 array with 13x1TB drives. Within 10 minutes 3 of these drives fell out of the array... we assume bad cable to the controller card and replaced, however now we need to get the ...
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1answer
1k views

Ubuntu RAID5 Software Raid inactive - unable to boot into Ubuntu from non-raid drive

I have a server with 6 disks in it, 5 of which are in a RAID5 array. I came home from work today to find that the landlord had been through the house with a sparky, and the power had been reset. Now, ...
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1answer
1k views

Ubuntu software raid on efi, how to boot off second drive?

I'm up and running on Ubuntu server with software raid 1 with 2 500GB drives and I'm just trying to test things out. If I unplug the second drive I'm able to boot in degraded mode but if I unplug the ...
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3answers
4k views

Deciphering continuing mpt2sas syslog messages

Summary I have been getting these cryptic messages in syslog since I installed some new hardware and I can't figure out what the problem is, if it's serious, or what to do about it. They're from the ...
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1answer
877 views

Why does heavy I/O slow my server to a crawl?

I've been trying to troubleshoot a problem with I/O on my disks. The setup is as follows: OS: CentOS 5.6 Disk layout: Disks (/dev/sda, /dev/sdb) Partition (/dev/sda1, /dev/sdb1) MD Array (RAID-1) ...