All Questions
122
questions
36
votes
10
answers
238k
views
How to get an inactive RAID device working again?
After booting, my RAID1 device (/dev/md_d0 *) sometimes goes in some funny state and I cannot mount it.
* Originally I created /dev/md0 but it has somehow changed itself into /dev/md_d0.
# mount /...
- 5,790
32
votes
6
answers
29k
views
Does RAID1 increase performance with Linux mdadm?
I have a cheap 2-bay NAS with a 2TB HDD. To be robust against disk failure, I'm thinking of buying a second 2TB HDD and putting it in RAID1 with Linux mdadm. The file system is ext4.
Will this ...
- 843
32
votes
11
answers
61k
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 ...
- 19.7k
28
votes
4
answers
65k
views
How-to change the name of an MD device (mdadm)
Here is the output from mdadm -Esv:
ARRAY /dev/md127 level=raid0 num-devices=2 UUID=d89d9d45:9a420812:c44c77eb:7ee19756
devices=/dev/sdb8,/dev/sda8
This is a v0.90 array. The question is as ...
- 1,469
13
votes
5
answers
12k
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 ...
CapnBFG
11
votes
1
answer
13k
views
How can I remove this "zombie" mdadm array?
Admittedly I'm not too familiar with MDADM. I recently set up an array for a NAS, but incorrectly sized the partitions in my setup script, and need to remove the array, re-partition the disks, and re-...
- 399
9
votes
3
answers
4k
views
Can I use an entire drive for as a software raid member?
Can I use /dev/sda and /dev/sdb for my RADI1 configuration?
Or do I first have to partition both with a single Linux raid partition?
- 740
9
votes
3
answers
9k
views
Is it safe to put harddisks of a md-software-raid to standby?
I have a home-fileserver with 6 desktop harddisks in a md-raid.
The server isn't accessed a lot, so I think it would be good for the harddrives to go in standby-mode after some idle time (e.g. with ...
- 113
9
votes
1
answer
2k
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 ...
- 759
8
votes
1
answer
8k
views
Possible mdadm RAID states?
I'm writing a monitoring plugin for a home server RAID, mdadm on Ubuntu 10.4.
Using sudo mdadm --detail /dev/md0
I get output like this:
/dev/md0:
Version : 00.90
Creation Time : Thu Dec ...
- 1,279
8
votes
3
answers
7k
views
Raid1 with active and spare partition
I am having the following problem with a RAID1 software raid partition on my Ubuntu system (10.04 LTS, 2.6.32-24-server in case it matters).
One of my disks (sdb5) reported I/O errors and was ...
- 81
7
votes
1
answer
3k
views
Fail device in md RAID when ATA stops responding
I had created five 1TB HDD partitions (/dev/sda1, /dev/sdb1, /dev/sdc1, /dev/sde1, and /dev/sdf1) in a RAID 6 array called /dev/md0 using mdadm on Ubuntu 14.04 LTS Trusty Tahr.
The command sudo mdadm ...
- 19.7k
6
votes
4
answers
4k
views
Linux software RAID robustness for RAID1 vs other RAID levels
I have a RAID5 array running and now also a raid1 that I set up yesterday. Since RAID5 calculates parity it should be able to catch silent data corruption on one disk. However for RAID1 the disks are ...
- 1,260
6
votes
3
answers
24k
views
Creating a RAID1 partition with mdadm on Ubuntu
I'm trying to set up a RAID1 partition on my Ubuntu 9.10 workstation.
On this dual-boot system, Ubuntu is running from a separate drive (/dev/sdc - an SSD that is quite small, which is why I need ...
- 5,790
6
votes
1
answer
504
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. ...
- 191
5
votes
1
answer
538
views
Mount Btrfs raid 5 from failed ReadyNas 104 on Linux - aka how I restore data from my ReadyNas
After about 7 years my ReadyNas finally failed, I would expect from Neatgear detailed recovery instruction, but I read dozens of threads - my problem is not uncommon, but solution was not found.
After ...
5
votes
2
answers
4k
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 ...
- 353
4
votes
1
answer
4k
views
MDADM RAID-0 does not increased size after grow on AWS Linux with EBS
I wanted to grew a Raid0 from 2 disks to 3 (each 1TB EBS on Amazon AWS) but the size did not change thereafter. The RAID started with two disks sdc and sdd and the new one was sdf.
Here is the grow-...
- 193
4
votes
2
answers
6k
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 ...
- 2,226
4
votes
1
answer
13k
views
Does mdadm record array event history?
I received an automated email from the mdadm daemon:
A Fail event had been detected on md device /dev/md0.
It could be related to component device /dev/sdh.
I find the wording strange. "could be"? ...
- 358
4
votes
1
answer
1k
views
HDDs occasionally "click" and dump this error
Every once in a while, my HDDs (6 1TB drives in a Linux md RAID-6 array) make a brief "click" sound, and I get this from dmesg. I don't really have any clue how to start diagnose this, or even how ...
- 152
4
votes
0
answers
3k
views
How to prevent an mdadm array check from consuming excessive system resources?
Once a month I've been doing
echo check > /sys/block/md2/md/sync_action
in order to force a software raid consistency check. The problem is this is a 7.2T RAID 5. The consistency check takes ...
- 181
4
votes
1
answer
758
views
Raid Spare Spin Down
I have a software RAID 5 array (mdadm under Debian Linux) that has been up for the better part of a decade and has seen it's fair share of drive failures. I've always been leery about setting up a "...
- 183
3
votes
1
answer
6k
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 ...
- 33
3
votes
4
answers
10k
views
MDADM reshape really slow
To sum up : My raid reshape with mdadm is really slow.
The complete story : 3 days ago I realized that one of my disks from a raid 5 array was faulty. I removed it and replaced it with a brand new ...
- 63
3
votes
1
answer
17k
views
Linux mdadm does not assemble array, but recreation of array does it
Maybe i'm not very clear in the title. When i'm trying to assemble my raid1 array with mdadm:
sudo mdadm --assemble /dev/md0 /dev/sdc /dev/sdd
It tells me that
mdadm: Cannot assemble mbr metadata ...
- 45
3
votes
0
answers
746
views
MD RAID 6 with XFS Periodic Kernel Panic -- Possible Kernel Bug?
This now appears to be a bug with the combination of MD and XFS after finding similar kernel panic reports elsewhere. A bug report with Ubuntu has been filed here ( https://bugs.launchpad.net/ubuntu/+...
- 715
3
votes
0
answers
3k
views
Synology DiskStation: How to stop/interrupt a running reshape (RAID5 -> RAID6)
The short of it: I have a running reshape from RAID5 with 5 disks to RAID6 with 6 disks which needs to be stopped, so I can power off the system. I do not care if the reshape needs to start fresh once ...
- 86
3
votes
0
answers
255
views
Linux Software RAID - Migrate from disk device to a partition
I have two 8TB disks configured as RAID1 using mdadm on Ubuntu 18.04 server. They way I created software RAID was on the whole device - /dev/sdb and /dev/sdc - instead of the partition such as /dev/...
- 31
3
votes
0
answers
185
views
Metadata of the assambled raid inconsistent with the metadata of the individual drives?
We have a raid 10 with two failed drives, with one drive from each set still functional.
When booting into rescue system the metadata seems to be fine and consistent with the expected state.
The ...
- 31
3
votes
1
answer
249
views
SSD failed, mdadm thinks the RAID0 array is fine
I have a RAID0 array created using mdadm in Debian. sdf is the drive that died.
$ cat /proc/mdstat
md4 : active raid0 sdf1[1] sde1[0]
468859904 blocks super 1.2 512k chunks
$ mdadm --misc --...
- 161
3
votes
1
answer
2k
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 ...
- 1,260
2
votes
1
answer
1k
views
Ubuntu server remove extra partition and resize current larger in mdadm RAID1
I am running an Ubuntu Server. Currently, I have the hard drive configuration shown below:
I want to remove the /mnt/winback partition and add the extra space to the /mnt/data partition. What is the ...
- 241
2
votes
1
answer
2k
views
"ext4lazyinit" running since 6 days on a new RAID5 array
I know there are a lot of "ext4lazyinit" topics. But they are all about 4-6TB HDD, and poster stating that it has in the end been completed after a few hours.
On my side i have a newly ...
- 293
2
votes
1
answer
6k
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 ...
- 21
2
votes
1
answer
2k
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 (http://en.wikipedia.org/...
- 21
2
votes
1
answer
184
views
How to recover a RAID 5 after deleting the partition table and fstab?
I have a RAID5 set up for my storage drives on my Nixos 23.11 machine. I followed this guide to set up the RAID (and I followed it very closely).
I have just reinstalled Linux on my boot drive (...
- 41
2
votes
1
answer
2k
views
how is mdadm executed during startup?
I think I read documentation/internet left to right, but I cannot see anywhere information, how is mdadm invoked during system startup. I cannot see anything in /etc/rcX.d, I cannot see any systemd ...
- 583
2
votes
1
answer
2k
views
Why did mdadm disable a disk on my raid array?
In syslog I see:
Jun 3 15:07:12 storage kernel: [36518.430143] md/raid1:md0: Disk failure on sdd1, disabling device.
Jun 3 15:07:12 storage kernel: [36518.430143] md/raid1:md0: Operation continuing ...
- 147
2
votes
3
answers
2k
views
RAID-1 and regular drive removal (using RAID-1 as a backup measure)
Is using mdadm's RAID-1 of 2 partitions (one on laptop's internal HDD, one on external HDD) a good idea.
I want the system to work as RAID-1 if both drives are present, work as regular volume (...
- 17.3k
2
votes
0
answers
145
views
Mounting External Intel Raid Device on Linux Failing, No Suitable Superblock and Read Past End
I have a hard-disk from a dead machine that I'm trying to mount on my Linux machine. For reference, I'm using Fedora 39 and mdadm v4.2. First, I tried just mounting it, correctly showing it's a RAID ...
- 221
2
votes
0
answers
445
views
Mayhem with partitions and GPT: mdadm RAID overwritten by Windows partition - possible to fix partition table?
dear Community,
I’m writing as I may have wrecked my system up.
I launched disk manager in Windows; as one of my disks was not recognized, and as Windows kindly suggested me to initialize the-said ...
- 21
2
votes
0
answers
266
views
Raid6 mdadm reshape operation interrupted - now cannot mount or examine
Edit: Once the reshape finished the drive became fully accessible again.
I had a power failure while a raid6 array was being reshaped, and now certain operations cannot be run against it, including ...
- 279
2
votes
0
answers
52
views
Sata 2 vs Cacheless SAS6G JBOD Performance
I have some "old" servers here, using Asus P9D-MH/SAS/10G-DUAL
https://www.asus.com/Commercial-Servers-Workstations/P9DMHSAS10GDUAL/
This board comes with a SAS 6Gbps controller, an LSI SAS2308 ...
- 37
2
votes
1
answer
3k
views
mdadm shows inactive raid0 array instead of degraded raid6 after disk failure
I've been running an Ubuntu 18.04 system with an 8-disk raid 6 array, that crashed while having a faulty disk (I only noticed that there was a faulty disk after the crash). The raid array has survived ...
- 21
2
votes
2
answers
2k
views
raid 1 badly detected as raid 0 when one drive is missing
I'm learning raids, so maybe this is some basic question, but it's not covered anywhere...
When I create raid 1, update /etc/mdadm/mdadm.conf as[1], run update-initramfs -u, I can reboot and mount it....
- 583
2
votes
0
answers
2k
views
Recovering a Synology Raid 0 from Ubuntu (Healthy drives)
I am trying to remount a Synology raid 0 with 3x2GB drives. As far as I know, the drives are in healthy condition.
I simply don't have enough space to do a full image of these before I proceed, so I ...
- 21
2
votes
0
answers
949
views
RAID5 fails while recovering (mdadm): Any chance to resync?
My RAID5 is going to die because, while restoring a failed HDD, on another HDD read errors occurred and a restore is impossible. I just want to know whether it's possible to restore only a part of ...
- 21
2
votes
0
answers
421
views
Dual boot Win8/Linux on Asus Zenbook UX301 keeping intel imsm RAID0
I have Asus Zenbook UX301 with Win8 preinstalled. I would like to have a Linux installed in dual-boot configuration. However, Windows is using the notebook 2 SSDs as intel RAID0 (rom-based RAID, ...
- 121
2
votes
1
answer
4k
views
mdadm --examine displays something different than --detail
Who should I trust to fill my /etc/mdadm/mdadm.conf ?
mdadm --examine --scan returns /dev/md/0 while obviously it's /dev/md0 that is currently rebuilding
What should I put in my /etc/mdadm/mdadm.conf ...
- 441