0
votes
0answers
20 views

Linux MD software raid stripe cache size

From what I can piece together the /sys/block/md0/md/stripe_cache_size is for raid5 and 6 set at a very low default value to avoid starving machines for memory. By increasing this value you can get a ...
0
votes
0answers
25 views

mdraid 512/4096 sector confusion

I created a new mdraid array on 3TB disks, connected via USB (because the internal SATA ports were used for the old array). $ fdisk -l /dev/sdb Note: sector size is 4096 (not 512) Disk /dev/sdb: ...
0
votes
0answers
28 views

Build one logical drive from hdd and ssd drives (with a tweak!)

How is it possible to build one logical drive in linux from two physical drives, hdd + sdd with the below rules: All writes are replicated to both drives (Kind of RAID 1). All reads are only ...
0
votes
2answers
37 views

Failed Software RAID0 on Linux - Attempting to recover data

I have a two disk RAID0 software raid (not hardware raid) that is reported to have failed during boot and my OS won't start. Using a Live CD, I get the following output : sudo mdadm -E /dev/sdc1 ...
0
votes
0answers
37 views

mdadm raid 6 stuck on rebuilding

I have a raid 6 running consisting of 9 1TB drives. Some time in the last couple of days, one of them became faulty and the raid startet rebuilding. But apparently it is stuck ... This is the raid: ...
0
votes
0answers
44 views

How to set boot disk after disabling mdadm raid 1?

I had two disks in raid 1. The device contained the whole system. Disabled it from a rescue disk with: (there were three partitions) mdadm --stop /dev/md1 mdadm --stop /dev/md2 mdadm --stop /dev/md3 ...
3
votes
0answers
56 views

mdadm: Win7-install created a boot partition on one of my RAID6 drives. How to rebuild?

My problem happened when I attempted to install Windows 7 on it's own SSD. The Linux OS I used which has knowledge of the software RAID system is on a SSD that I disconnected prior to the install. ...
1
vote
0answers
39 views

Redundancy: LVM+mdadm or LVM internal RAID

The task is to create LVM storage for virtual machine images. So LVM will be used in any case. There are two ways LVM providing redundancy: block mirroring lvcreate -m 1 --mirrorlog mirrored -n ...
0
votes
0answers
79 views

mdadm partiton not large enough to join array

I've used Linux on and off for the last many years, mainly as dual boot or as Virtual Machines, but when I decided to build a Dev Laptop I though I'd bite the bullet and put Linux on as the base OS. ...
0
votes
0answers
97 views

Hybrid Raid-1 HDD + SSD — Write Intent Bitmap

I am currently running a laptop with 1 HDD and 1SSD. I currently am using mdadm to put some partitions in a raid 1 configuration with --perfer-write set on the HDD. I have this working correctly ...
1
vote
0answers
26 views

Is there a safe way to move a partition beneath a linux software RAID5 using mdadm?

Suppose, for example, that you have a RAID5 across multiple disks and you would like to retire the oldest of the disks and replace it with something from this decade. I know I can fail the partition ...
0
votes
1answer
75 views

Recover software RAID

I built a RAID-1 with two hard drives using mdadm. Command used was: mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdb /dev/sdc it went fine, I create partition table and partitions in ...
0
votes
1answer
96 views

mdadm --assemble fails when /dev/sd[abcde]1 reordered

I am having trouble assembling a small RAID5 due to a recurring reordering of /dev/sd[a-f] on boot (Debian7). md0 was initially using sd[abc]1, it contains a LUKS device, which in turn contains a ...
1
vote
0answers
185 views

XFS: Mount overrides sunit and swidth options

I have a 9TB XFS partition consisting of four 3TB disks in a RAID-5 array with a chunk size of 256KB, using MDADM. When I created the partition, the optimal stripe unit and width values (64 and 192 ...
1
vote
0answers
160 views

mdadm: faulty Array, how to get recover as much as possible?

I have a RAID5 with 4 Disks in my PC. All of them were healthy (and the RAID itself) until before. I tried to install windows 8.1 which automatically creates this "SystemReserved"-Partition. The ...
1
vote
2answers
61 views

What are the risks of running a software RAID 1 array in degraded mode?

I'm replacing my workstation's system drive and would like to in the future be able to easily add a second drive to form a proper (although software) RAID 1 mirror. For the time being, however, I'm ...
0
votes
1answer
173 views

RAID10 Recovery

I had a RAID10 array fail a few nights ago, I have to admit that I am fairly lost on all of this. I have googled this extensively and I don't understand what is going on. If anyone here can provide ...
0
votes
1answer
124 views

Adding sda1 vs. sda to a linux software raid

I'm running a Linux md software RAID 6 on several USB hard-drives. Each drive is partitioned to contain one partition of type fd (linux raid). My RAID is built on these partitions, i.e. it uses sda1, ...
0
votes
1answer
54 views

How do I prevent anacron from running certain scripts?

I am running RHEL5 and software RAID (mdadm). Currently I allow the 99-raid-check weekly cron script to run at the normal time (early Sunday morning). However, if the system is off during that time it ...
1
vote
1answer
448 views

Assembling an mdadm array with “possibly out of date” disks

I've recently moved house and have had some power problems after switching on my file server that's using a mdadm RAID5 set up. The file system I'm using is ext4. It seems that at some point two (of ...
1
vote
2answers
306 views

/dev partition missing, so mdadm broken. How to get Linux to see partition?

Upgraded a Linux box and changed out the root drives. There was a RAID-5 array of three SATA drives that I moved over (not root). Reinstalled the OS but was CentOS 6.4 before and after. # mdadm ...
1
vote
0answers
163 views

Create a mdadm raid mirror of an existing lvm

Hello I'm trying to figure out how I can create a pretty strange mdadm mirror of my lvm. I have 4 disks, (sda,b,c,d). Each disk has 2 partitions: 1Gb - physical volume 500mb - Swap My system lvm ...
5
votes
1answer
118 views

Is it safe to “use” to disk if extended smart check is in progress?

As simple as the title suggests. /dev/sda is a unit from /dev/md127 - RAID1 drive. I'm currently running a test - started a smartctl -t long /dev/sda. Afterwards, I started to copy files over ...
1
vote
0answers
110 views

Is `dmsetup remove` safe with respect to contained data?

I have a "lost" SW RAID array as described in this question: http://askubuntu.com/questions/311024/raid1-array-lost-after-upgrade-from-ubuntu-11-10-to-13-04. I have now identified a way to mount one ...
1
vote
1answer
213 views

Documentation for mdadm bad block support

I've read a bit about that mdadm (and the kernel) now have bad block support but I am having a hard time finding any useful documentation on this subject. Is the bad block list for disk X duplicated ...
1
vote
0answers
177 views

Upon reboot, Linux software raid fails to include one device of a RAID1 array

One of my four Linux software raid arrays drops one of its two devices when I reboot my system. The other three arrays work fine. I am running RAID1 on kernel version 2.6.32-5-amd64 (Debian Squeeze). ...
0
votes
2answers
68 views

Writing to a specific drive with software RAID4 on Linux

Edited to reflect conclusions from comments: I want to construct a software RAID-like array with 2 storage devices plus one parity device, where the parity device maintains the XOR of the two other ...
3
votes
2answers
11k views

How do I reactivate my MDADM RAID5 array?

I've just moved house which involved dismantling my server and re-connecting it. Since doing so, one of my MDADM RAID5 arrays is appearing as inactive: root@mserver:/tmp# cat /proc/mdstat ...
2
votes
0answers
491 views

mdadm RAID monitoring no DegradedArray email

So, I have a couple of MDADM RAID arrays and I want to set up monitoring with email notifications for drive failures through sSMTP but I can't seem to get it working. The system in question is a ...
0
votes
1answer
1k views

mdadm disk partition type : Linux RAID Autodetect mandatory or 83 Linux ok?

Main question : Q1: i would like to know when using mdadm, the "Linux RAID Autodetect" type is mandatory for my disk, or a "83 linux" type is ok ? Sub question : Q1_1 : What are the differences ? ...
2
votes
1answer
89 views

Why make a partition at all for mdadm/raid?

i have 4 disks, sd[a,b,f,g] of various sizes that I want to 'merge' together. I am using mdadm to achieve this. my question is, what's the difference between -- mdadm --create /dev/md0 ...
3
votes
1answer
1k views

Need to find which drives are mirrored within RAID-10 array

I have a home media server running on openSUSE 12.2. I'm using eight 2TB drives in a RAID-10 configuration. I deliberately bought two different types of drives: four Seagate Barracuda Green and four ...
1
vote
0answers
445 views

Unable to reassemble md raid on drives pulled from ReadyNas Duo v1

I'm toying with a ReadyNAS device that I've recently acquired. It is a SPARC-based box, and it runs linux. As device is pretty slow, I've pulled one drive out of array, hoping to populate it with ...
2
votes
1answer
623 views

Mounting a raid1 device - no suitable drives found

I'm having some problems with my disks; long story.. but right now I'm trying to mount a device that was part of a 2-disk raid1. For that, I tried to assemble it into a new array, but... % mdadm -Av ...
0
votes
2answers
818 views

In mdadm's /proc/mdstat, what does [U_U] mean?

I just set up a raid 5 array for my media server. I set got 2 new disks, and set up an array with one missing drive, to copy the data from the old single drive to the new array, and later I will add ...
2
votes
1answer
820 views

Optimal raid array on Centos 6

I have 4x2TB disks and I want to create a well-performing RAID5 array (server is HP N40L microserver with 8GB RAM, booting from a 64GB SSHD). The OS is Centos 6.3, x86_64. I created the raid array ...
1
vote
1answer
371 views

Linux raid10 on btrfs

I've read that BTRFS requires at least 4 disks (https://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices). Indeed, Linux mdadm raid10 requires only 2 disks ...
2
votes
1answer
1k views

Degraded RAID5 and no md superblock on one of remaining drive

This is actually on a QNAP TS-509 NAS. The RAID is basically a Linux RAID. The NAS was configured with RAID 5 with 5 drives (/md0 with /dev/sd[abcde]3). At some point, /dev/sde failed and drive was ...
0
votes
0answers
219 views

Post raid5 setup reboot shows single hard drive failure on ubuntu 12.10?

I just set up raid 5 on linux using three HDDs as per a guide. It all went fine until when I rebooted I got the following text: http://i.stack.imgur.com/Zsfjk.jpg. Does this mean one of my HDDs has ...
0
votes
1answer
547 views

Linux system cannot find RAID 10 md device after reboot of the system

I ran these commands: $ sudo mdadm --verbose --create /dev/md0 --level=10 --chunk=256 --raid-devices=4 /dev/sdh1 /dev/sdh2 /dev/sdh3 /dev/sdh4 $ echo 'DEVICE /dev/sdh1 /dev/sdh2 /dev/sdh3 /dev/sdh4' ...
0
votes
1answer
99 views

How to create physical and logical volumes on system reboot

My system is set up so that I take four devices, create a RAID 10 array out of them, create a physical volume, a volume group, and then three logical volumes, and lastly I create filesystems out of ...
3
votes
0answers
1k views

Does TRIM avoid the performance impact of mdadm RAID 1 on SSD?

It has already been mentioned in other questions that Red Hat recommends against using mdadm RAID 1 on SSD. Red Hat also warns that software RAID levels 1, 4, 5, and 6 are not recommended for use ...
0
votes
0answers
48 views

Do a Re-Build During a Re-Shape?

On my Linux software RAID 6 array, I'm currently mid-reshape and 2 drives have been marked as failed. I've swapped them out and added new ones to the array, which are currently marked as spares. The ...
0
votes
1answer
80 views

Linux RAID Re-Shape Stopped

For the past 8 hours my mdadm re-shape process has been stuck. The output is: Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] md0 : active raid6 sdo[11] ...
2
votes
0answers
7k views

How to force mdadm to stop RAID5 array?

I have /dev/md127 RAID5 array that consisted of four drives. I managed to hot remove them from the array and currently /dev/md127 does not have any drives: cat /proc/mdstat Personalities : [linear] ...
1
vote
1answer
2k views

mdadm: superblock on /dev/sdd1 doesn't match others - assembly aborted

OS: Debian Squeeze Kernel: 2.6.32-5-amd64 mdadm version: 3.1.4 (31 August 2010) mdarrays md1 = raid1 (this is working) (devices: /dev/sd[fg]1) md0 = raid6 (previously raid5, ...
1
vote
2answers
337 views

Migrate mdadm raid array from 32bit to 64bit debian squeeze

I have a raid5 array running on Debian Squeeze 32bit (x86) and I plan to upgrade to Debian Squeeze 64bit (amd64). To keep my raid5 array and ext4 filesystem I simply keep a copy of my mdadm.conf ...
1
vote
1answer
3k views

How do I tell mdadm to start using a missing disk in my RAID5 array again?

I have a 3-disk RAID array running in my Ubuntu server. This has been running flawlessly for over a year but I was recently forced to strip, move and rebuild the machine. When I had it all back ...
17
votes
7answers
19k views

Simple mdadm RAID 1 not activating spare

I had created two 2TB HDD partitions (/dev/sdb1 and /dev/sdc1) in a RAID 1 array called /dev/md0 using mdadm on Ubuntu 12.04 LTS Precise Pangolin. The command sudo mdadm --detail /dev/md0 used to ...
0
votes
0answers
545 views

mdadm recognizing array incorrectly how can I recover the data

So I formatted both disks sd[cd], each as a big ext4 partition, and then used mdadm to create a raid0 array sd[cd]1. This worked fine, and I mounted the device and started storing data on it. Prior to ...