Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [mdadm]

A linux utility used to manage software RAID devices.

844 questions
3
votes
1 answer

Cannot get at data in my NAS

I've got a bit of an issue that I'm hoping you can help me with. I have an Iomega ix4 as my NAS. This runs Linux and each drive in the box has 2 partitions: one for the OS and RAID info, and the second for the actual data. I had it configured as…
Ben
  • 31
  • 1
3
votes
2 answers

mdadm - Recovering a 'split' RAID1 array

I have two drives that used to be part of a single RAID1 volume but it appears that one of them went offline for some time, something I've noticed just now when I rebooted my system. I now seem to have two RAID volumes, as reported by: # cat…
Hamza
  • 153
  • 4
3
votes
2 answers

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 drive. Has some partitions on it that boot the system…
zimmy6996
  • 31
  • 1
  • 2
3
votes
1 answer

Creating Persistent Drive Labels With UDEV Using /dev/disk/by-path

I have a new BackBlaze Pod (BackBlaze Pod 2.0). It has 45 3TB drives and they when I first set it up they were labeled /dev/sda through /dev/sdz and /dev/sdaa through /dev/sdas. I used mdadm to setup three really big 15 drive RAID6 arrays. However,…
Matt Mencel
  • 369
  • 5
  • 13
3
votes
1 answer

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, each based on 5 500GB partitions. The RAID-5…
Adam Ryczkowski
  • 720
  • 1
  • 9
  • 29
3
votes
0 answers

four-disk md raid10-far can be assembled and ran as "clean, degraded" with only 2 disks. Bug or i'm missing something?

Today i was solving raid failure on raid10-far with four disks. One disk failed and another wasn't re-added after a hard reboot. The mdadm -D was reporting it's clean and running with only two out of four disks. When i tried to read the md array…
Koubas
  • 51
  • 3
3
votes
1 answer

Linux raid controller (LVM/MDADM)

Today I'm in a very bad place. A production raid array went down. The controller failed. After unmounting the file systems and killing all processes, I changed the hardware controller. On restarting the array the disks have come back and I want to…
user131012
  • 71
  • 1
  • 4
3
votes
2 answers

Reading off of MDADM drives after server died

I had a 2-drive RAID-1 array running on ubuntu, which I had forgotten about. The host I was running them on is now dead, leaving me with these two disks. How can I get data off of them? If I dump them- using dd or the such- how can I read that data…
alicht
  • 33
  • 3
3
votes
1 answer

LVM incorrectly reported missing after power failure

We have had a major power failure in the data-center. We are using a set of servers for our storage needs. The main server has several pairs of disks mirrored with mdadm. The resulting /dev/mdX are LVM physical volumes and belong to a big…
mensi
  • 189
  • 1
  • 12
3
votes
2 answers

Raid 5 with 4 disks on Debian automatically creates a spare drive

I'm trying to to create a RAID 5 with 4x 2TB disks on Debian 6. I followed the instructions from: http://zackreed.me/articles/38-software-raid-5-in-debian-with-mdadm I created the raid with following command: sudo mdadm --create --verbose /dev/md0…
R.S.
  • 161
  • 1
  • 6
3
votes
3 answers

mdadm raid5 too slow when writing

I have set up a RAID5 array using 4 disk partition. All disks are 2TB. When the RAID5 array was initially syncing it was too slow. So I did a echo 32768 > /sys/block/md2/md/stripe_cache_size and then it was quiet fast. But still it took a days time…
proy
  • 1,229
  • 10
  • 10
3
votes
0 answers

How do I create a RAID10 array using EBS on Amazon?

Basing this question on information I got in Why does df shows only half the size of a RAID10 array?, how should I create a RAID10 array using EBS volumes on Amazon, in a way that will not be redundant too much ? As the linked question shows, I was…
Doron
  • 543
  • 1
  • 6
  • 14
3
votes
0 answers

mdadm LBA mapping

I am trying to write a script similar to mdtrim (https://github.com/Cyberax/mdtrim) for a raid 0 software raid through mdadm. The mdtrim is for raid 1 only at the moment, and it works by writing a large, mostly empty file to the file system, finding…
Ivan
  • 173
  • 6
3
votes
1 answer

Unresponsive mdadm

I have a raid 5 mdadm raid array set up with 6 drives and a hot spare on an Ubuntu 11 server. There are a couple samba shares on the drive, and until today, they were working well. A couple hours ago users started noticing their shares were crawling…
Andy Miller
  • 133
  • 1
  • 7
3
votes
1 answer

Software RAID1 ready to fail - How can I degrade manually?

I have a Centos 5.4 server in production with 2 drives in software RAID1. The last days /var/log/messages has a lot of messages, showing that one of the drives is ready to fail: Sep 23 00:48:38 milkyway kernel: SCSI device sda: 1465149168 512-byte…
Hik
  • 33
  • 2
1 2 3
…
56 57