A linux utility used to manage software RAID devices.

learn more… | top users | synonyms

0
votes
0answers
12 views

Can't rebuild a linux RAID array after replacing disk, “mdadm: Cannot open /dev/sdb1: Device or resource busy”

I have replaced a failed drive in my server with a new one, and wish to add it back to the array. I am getting the following error, what can I do to resolve this? [root@la ~]# cat /proc/mdstat ...
2
votes
1answer
25 views

what is the purpose of mdadm's check command?

I discovered one of my servers running slower than usual today because of the checkarray launched by a cronjob installed by default on the server. This is Ubuntu 14. In this particular case, I have ...
2
votes
0answers
60 views

mdadm: Convert RAID10 to RAID1

The machine in question is equipped with 4x ssd, and running Debian wheezy 7.8, linux kernel 3.2.0-4, mdadm v3.2.5. Currently I'm using a RAID10 consisting of all these ssd. I've to increase the ...
0
votes
1answer
35 views

Repairing RAID6 with two drive issues mdadm

I have had two disk failures on my RAID6 array. I have added two new disks and did the following: I ran mdadm /dev/md1 --remove on the two disks I set up my RAID on the 1st partition of each disk ...
3
votes
1answer
77 views

Best way to RAID 4 x Intel SSD 910 for PostgreSQL

I have a Linux (debian/ubuntu) server with 4 x Intel SSD 910 800GB pcie that I need to RAID together. The biggest problem with these card is that they give you 4x200GB drives that you cant ...
3
votes
0answers
39 views

Why is my HDD partition a character special device?

I have a bunch of old 1T disks with an mdadm array on them. They had been out of commission for awhile, but yesterday I slotted them into a server running an up to date Debian Jessie. Eventually I ...
1
vote
0answers
41 views

How to best use Amazon's “ephemeral” SSD devices under Linux? [closed]

Amazon attaches "ephemeral" SSD device(s) to most of the instace-types -- these are included in the cost of VM, are fast, but any data on them is lost, when the VM is shut down. How to make the best ...
0
votes
1answer
20 views

How to Mounting RAID0 EBS Volumes after reboot on EC2?

I've already attached two volumes to my EC2 instance and configured RAID0 for them. After a reboot, the volumes didn't re-attach. I thought I had configured them to attach on reboot in fstab but they ...
0
votes
2answers
17 views

Move an ext3 fs to a larger mdadm array in one step

I have an ext3 fs on an mdadm array of 1TB disks on an openSUSE system, and I want to move the fs to a new array of (the same number of) 3TB disks. I can have the system running with this fs ...
2
votes
1answer
50 views

Linux: Rebuilding software Raid 1 fails when adding partition

I had an issue yesterday with a software Raid, where one disk had to be replaced. I removed the partitions from the array using mdadm /dev/mdx -r /dev/sdbx After the failed drive has been replaced ...
-2
votes
1answer
22 views

Raid-5 Linux Software array, 3 drives “removed”

I have a raid array with several drives marked as removed. I want to add them back in, but am not sure how to do so. [root@tera2 ~]# mdadm --detail /dev/md3 /dev/md3: Version : 1.2 ...
0
votes
0answers
24 views

Not sure how to change primary partition size and add a new partition on a software RAID1 using mdadm, as well as parted or fdisk?

I'm trying to create a /data partition to run drbd. However the drbd guide only shows steps for an fdisk on a normal disk, and not mdadm software raid. So I have sda3/sdb3, which are holding ...
0
votes
0answers
25 views

Transient errors on Linux RAID1 and RAID10

On the Arch Linux wiki you can read: Due to the fact that RAID1 and RAID10 writes in the kernel are unbuffered, an array can have non-0 mismatch counts even when the array is healthy. These non-0 ...
1
vote
1answer
103 views

Mounting device from degraded RAID 1

I am trying to mount device form raid 1 (created on other device), because I need to copy data from this disk. When I am trying to assemble new array i get a message: foo@bar# mdadm -A -R -v ...
0
votes
1answer
55 views

Ubuntu Software RAID 1 with NTFS weird volumes on RAID Array

I'm trying to mirror two secondary 2TB HDDs with RAID 1 with 1 big NTFS partition and am coming cross something that looks weird to me, although it could just be my complete ignorance because this is ...
6
votes
1answer
253 views

RAID rebuilding seems to have stopped

My server was running a RAID 1 array with two disks. One of those disk failed today and was replaced. I've copied the GPT partition to the new hard disk (sda) with: sgdisk -R /dev/sda /dev/sdb ...
0
votes
2answers
76 views

How can I force soft raid to read only from one disk?

I have quite a large IO wait showing in top. I suspect this is fault of SDA drive (on of 2 disks in RAID array), which was replaced about week ago. There are no errors visible, smart showing nothing, ...
1
vote
1answer
48 views

Remote system's filesystem disappeared after “mdadm --grow 2 /dev/md0”?

Yesterday, I added a second 500GB hard drive to a system. This system was installed as a RAID-1 system with only one drive, because I didnt have the other one on hand. After finally adding the second ...
0
votes
2answers
26 views

How do I list which drives are part of each RAID array?

I have a linux software RAID using md. I want to list all of my RAID arrays and each hard drive attached to them. Is there an easy way to do that?
-1
votes
1answer
44 views

Can't mount raid 1 with different size disks

I have a EC2 instance with a an ssd on xvdm (20 gb, 60 iops) and another ssd on xvdb (16 gb, better iops - instance store). The xvdm contains a mysql database and I'm trying to join these 2 disks in a ...
0
votes
1answer
26 views

mdadm isn't rebuilding the array

I recently replaced a drive (/dev/sdb). All arrays have been rebuilt correctly except for one of them (/dev/md2). There is no problem with the new drive. Partitions are OK. mdadm says it's "spare ...
0
votes
0answers
57 views

mdadm/grub2/lvm boot failure if all drives are physically connected

Weird problem here. I've got a Debian 7 server (quad core, 32GB RAM) that runs a whole bunch of VMs. The main boot drive is a RAID 1, with an LVM volume group called System, which contains a bunch of ...
1
vote
1answer
70 views

Ubuntu server becomes unresponsive on hard disk issues despite raid setup

I am running a server on Ubuntu 10.04.4 LTS (Linux xxxx 2.6.32-67-server #134-Ubuntu SMP Wed Sep 24 18:55:00 UTC 2014 x86_64 GNU/Linux) with two hard discs in a software raid 1. I repeatedly had the ...
-1
votes
1answer
225 views

How to add software RAID-1 to an existing system?

I couldn't find any tutorials for converting a non-RAID Linux system (Ubuntu 14.04 in my case) into a disk-level RAID-1 system after installing a second disk (/dev/sdb) Is the following correct? ...
0
votes
1answer
49 views

Analyze SMART self-test for broken disks [closed]

I recently came home from vacation only to wake up the following morgon with two disks in my RAID5 array marked as faulty. I was able to start the RAID by forcing it to use the faulty disks and run, ...
0
votes
0answers
33 views

Increase space on RAID 10

I have a RAID10 with 7 working devices ,4 actives and 3 spares .I want to increase the RAID's space from 4 devices to 6 . i use this : sudo mdadm --grow --raid-devices=6 /dev/md0 but it gives me ...
1
vote
0answers
154 views

To write in mdadm.conf in initramfs prompt doesn"t not save changes after reboot

I made a mistake with my mdadm.conf with my debian backup server. I used this command : mdadm --detail --scan --verbose >> /etc/mdadm/mdadm.conf to add a raid5 (it works great). By using ...
0
votes
0answers
23 views

Order of execution: First file system, then array vs. first array, then file system

Suppose I have two HDDs, same manufacturer, same model, same attributes (volume, speed, cache, ...). Both are equally partitioned. I want to have a level one array of two disks with one ext4 ...
2
votes
1answer
115 views

mdadm RAID6 to RAID60

Is it easy to convert a RAID6 to a RAID60? Right now, I have an 8-drive RAID6. I'm looking to upgrade to a 3U 16-bay system and thinking of having a 16-drive RAID60. Is it possible to move my ...
0
votes
0answers
78 views

mdadm: can't remove broken drive from raid1

I have a ubuntu server Ubuntu 12.04.5 LTS (GNU/Linux 3.2.0-34-generic x86_64) that uses a software raid with 2 physical drives. Apparently, one drive is unresponsive, and I try to remove it from ...
1
vote
1answer
78 views

Disabling damaged RAID 1 to read from healthy HDD

One of the HDDs in my software RAID 1 on a dedicated server is damaged. The customer support is slow to respond. I would like to transfer all data I need to another server, but file access is ...
0
votes
2answers
2k views

Grub rescue, will not boot from mdadm RAID, no such disk or device — mduuid wrong?

I am running a 14 disk RAID 6 on mdadm behind 2 LSI SAS2008's in JBOD mode (no HW raid) on Debian 7 in BIOS legacy mode. Grub2 is dropping to a rescue shell complaining that "no such device" exists ...
1
vote
1answer
40 views

MDADM - Raid 1 - Change a disk with a smaller one

I have a Ubuntu server with the operating system installed on a raid1 created with two 500GB devices. the second drive failed. I now how to replace it, but my goal now is to move the operating system ...
2
votes
1answer
565 views

Cannot install grub, segmentation fault, unable to identify filesystem, superfluous RAID member, found two disks with same index — Debian 7

A server was recently transported from location A to B, a long journey that took six months. Things have gone wrong due to nothing being labeled prior to shipment. Yes, I know --- it was done by ...
0
votes
0answers
49 views

mdadm - unable to reconstruct the raid1

When restarting my server, it (sometimes) fails to reconstruct my RAID-1 array (2 disks). My server, a 10-year-old computer, often changes sda into sdb or sdc which seems to annoy mdadm. When it ...
0
votes
0answers
64 views

Resizing a software RAID remotely, no LVM, / partition

I have a server that has a software RAID without LVM. That is only mdadm. There are the partitions /dev/sda2 and /dev/sdb2 which form /dev/md2. There is also a lot of space after both /dev/sda2 and ...
0
votes
0answers
254 views

mdadm RAID0 array recovery

I have a Linux file server with two 12-disk MD1000 disk arrays attached to a RAID controller. Unfortunately, a power blip has caused a loss of configuration data on the RAID controller and it is now ...
1
vote
1answer
69 views

Mdadm Raid10 - Files corrupt

I have a Raid10 array using software raid on 4*2-tb drives. My OS on this Raid array froze and when restarting my system via Ubuntu-CD i noticed the Raid array was gone. I assembled the raid array ...
0
votes
0answers
65 views

mdadm reattached a failed drive all by itself

I have 2 drives setup in mdadm mirroring (3 partitions on each drive). Last week the second drive (sdb) dropped out of the array because of some I/O errors I am still investigating. After a server ...
0
votes
1answer
49 views

External bitmap concerns

I am considering adding an external bitmap to my mdadm RAID6. The benefits seem absolutely incredible in terms of rebuild time but I do have some concerns. I didn't plan for it so I don't have much ...
1
vote
2answers
107 views

Should I partition a RAID or just create a file system on it? [duplicate]

Given a RAID 6 created from 6 drives /dev/md0 which should be used fully for data (no booting from it, root and swap are on a different drive), should I create one partition on that device and then ...
2
votes
1answer
4k views

Unable to mount '/dev/sda'

My server has two 2 TB hard disk drives in soft RAID 1. I can't mount /dev/sda. Output of parted -l root@rescue:~# parted -l Model: ATA HGST HUS724020AL (scsi) Disk /dev/sda: 2000GB Sector size ...
3
votes
2answers
970 views

Mdadm won't create an array larger than 10TB

I have a server with six 4TB drives running Ubuntu 14.04 LTS. One of the drives is used for the system/OS I wanted to use the other 5 drives to get as close to 20TB of storage as possible It's a ...
-1
votes
1answer
116 views

mdadm reports faulty disk, but smart doesn't find problems

I've got a 9 disk raid 5 array. Today i got a mail from my server: This is an automatically generated mail message from mdadm running on Eldorado A Fail event had been detected on md device ...
2
votes
1answer
91 views

MD RAID sector repair

This article states that RAID controllers are smart about unrecoverable read errors, and try to rewrite such sectors with the redundancy of the component drives. If the sector is bad, the disk's ...
0
votes
0answers
191 views

mdadm: All RAID disks look good, but can't access devices

Now, granted, issues with RAID rarely come up (at least with the one that I have to deal with in my life), so I'm not the most experienced person in the world. However, I'm not seeing any issues with ...
0
votes
2answers
80 views

soft raid6 recover second disk fault

I had a disk failure in a hosted system and had the failed drive replaced. During recovery, a disk error on a different drive occurred. when the original error occurred: md2 : active raid6 ...
1
vote
0answers
846 views

Ubuntu 14.04 mdadm issues on boot

I have a 14.04 Ubuntu machine which has: 2 x SSD in RAID 1 (md0) 3 x Sata HDD in RAID 5 (md1) The machine is set to boot from the md0 device. This machine has been running fine for a month or so, ...
3
votes
1answer
66 views

Reading /proc/mdstat

I just built my first raid5 yesterday (with 4 hds) and was reading about monitoring with /proc/mdstat. My understanding is an ideal dispaly with 4 drives should be [UUUU] however mine reads [UUU_]. ...
2
votes
2answers
1k views

Linux RAID 1: How to make a secondary HD boot?

I have the following RAID 1 on a Centos 6.5 server: # cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sdb1[3] 974713720 blocks super 1.0 [2/1] [_U] bitmap: 7/8 pages [28KB], ...