A linux utility used to manage software RAID devices.
Questions tagged [mdadm]
844 questions
-1
votes
1 answer
Linux RAID5 array error
I have two RAID5 arrays, 1 array for /boot and for /. The arrays both consist of three partitions:
MD0: /boot
MD1: /
My problem is, if I detached a disk (disappear) then mdadm prints that a drive went wrong. Okay no problem, but this message only…
Chaze
- 1
-1
votes
4 answers
4-Drive Software RAID1 vs RAID10 for Extreme Reliability Purposes
4-Drive Software RAID1 vs RAID10 heading tells you what I am contemplating about.
Hardware: 2x 1TB Enterprise-class HDDs + 2x 1TB Consumer-class HDDs.
OS and Software: Linux Debian Jessie (stable) with mdadm.
Intended purpose: Extreme reliability…
Vlastimil Burián
- 499
- 6
- 20
-1
votes
1 answer
mdadm --grow power failure, /dev/md2 no longer detected, RAID5
Did a terrible stupid mistake. Please advise me how should I best proceed.
My configuration is a RAID5 of 4x4TB drives. On top of it, LVM with various partitions including /, swap, everything. The configuration was quite automatic based on…
-1
votes
1 answer
Is it possible to recover a RAID 5 in this case?
Is it possible to recover a RAID 5? After losing the "/proc/mdstat" and run by mistake "mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1" instead of mdadm --assemble --scan.
juan
- 41
- 1
- 1
- 3
-1
votes
1 answer
Disaster recovery. MDADM/LVM2 Some advance but stuck on final mount
We made a stupid upgrade on a running server using wrong repositories and the system became totally unbootable.
The system, a SLES 11 we used a openSuse repository to upgrade, and everything went horribly wrong. It boots now only in (repair…
Marius Jensen
- 1
- 3
-1
votes
1 answer
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 raid 1 with write-behind to the slower disk. So…
Fluffy
- 171
- 1
- 10
-1
votes
2 answers
Recommended solution to join partitions (disks) into single partition
I have 4 hard disks (1 Tb each) on server.
It's debian wheezy, amd64.
Disks 2,3 and 4 are not partitioned yet.
I have to join them into single partition, it must be single filesystem/mountpoint for web application.
What is there best way to do this:…
Andrii Kupchanko
- 150
- 6
-1
votes
2 answers
What is the correct way to create new raid5 in Linux?
I added some new disks, and tried to create new array, using:
mdadm --create /dev/md/2 --level=5 -x 0 --raid-devices=4/dev/sd{a,b,c,g}2
It creates the array, but after reboot - it's gone. What should I do to keep it visible?
Also - I read about…
user195086
- 79
- 1
- 1
- 8
-1
votes
2 answers
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 systems.
I'd like to figure out "what is the RAID…
Achimnol
- 109
- 1
- 5
-1
votes
1 answer
Does linux software raid10 perform any data verification on each write?
I wand to find out is there any benefit in safety of storage data between manual sync(using cron & rsync) of two RAID0 volumes and RAID10 volume using Linux software raid. Does RAID10 preform any data integrity check during write operation?…
megadrofan
- 109
- 1
-1
votes
1 answer
Help, ive just corrupted my ext4 partition
After troubleshooting problems with my mdadm config and kernel settings for about a week now i got careless and left my data drives plugged in after a successful boot test.
i was attempting to change the MDADM super-block so the kernel would…
Silverfire
- 790
- 4
- 14
-1
votes
1 answer
mdadm array state not fully active - faulty device
I use 4 drives as a raid 5 on my Raspberry Pi. I shutdown my Pi every night and start the next morning. Sometimes the array appears to be faulty. Maybe the Pi doesn't properly mounts the drives correctly, but is not mentioning the problem in…
-1
votes
1 answer
mount: /dev/md0: can't read superblock
I have a Raid 5 with 4 disk and is not working, I can't detect what disk is failing for replacement
Could you help me?
Thanks in advance
Here is some information
root@debian:~# mount /dev/md0 /mnt/
mount: /dev/md0: can't read…
Daniel Segovia
- 1
- 1
-2
votes
1 answer
Hybrid RAID (SDD+HDD) gives unexpected results
I am doing some experiments with hybrid RAID in Linux.
My test consists of the following:
2x256GB SSD in RAID 0 (/dev/md1)
2x256GB HDD in RAID 0 (/dev/md2)
Then I made md1 and md2 into a RAID 1 (/dev/md127) and marking the slow HDD (md2) as…
Daniele Testa
- 661
- 4
- 10
- 18
-2
votes
1 answer
SSD DD write speed lower than HDD
I've come across a strange phenomena with a new dedicated server that's been provisioned.
The server has 2x1TB HDDs in software RAID 1 and a separate 120GB SSD that is intended to be used as a FlashCache drive. Both the spinning disks and the SSD…
rich1334
- 9