Questions tagged [mdadm]
A linux utility used to manage software RAID devices.
866
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Mdadm - Change RAID 10 chunk size and switch to "far" layout
I'm running an Ubuntu Linux NAS server with 4 2TB drives in software RAID 10.
I created the array during installation (with Ubuntu Server disc), but the layout is near and the chunk size is 64.
I ...
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Is mdadm Raid-1 Over A Network File Share Possible?
I am using 64bit CentOS 5.5
I know it's possible to set up software RAID1 using mdadm using a physical hard disk and a RAM disk.
Is it possible to set up software RAID1 with mdadm using a NFS mount ...
Travis
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Is there any way to build a linux software raid system without all drives?
I'm building a raid1 (ok it will probably be a raid10,f2 but the difference with 2 drives... isn't much) system with 2 1TB drives. However, 1 of the drives I've ordered is bad so I'm RMA-ing it. I'm ...
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Linux Raid: mystical md_d device
I have a 64bit Ubuntu Jaunty server (kernel 2.6.28-17-server) installed on two SATA disks (sdc and sde) in a mirror RAID, this being my current raid configuration:
cat /proc/mdstat
Personalities : [...
Norb
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mdadm - Drive has incorrect type after reboot
I have a raid 6 setup with six drives using mdadm. I noticed I had a failed drive (b) that was not responding at all. Making sure all drives are properly connected I stopped the raid, unmounted and ...
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Unable to remove the software raid-1 array when it is in degraded state
I want to remove the software raid-1 array [ when it is degraded state] configured on LVM in linux system and unable to remove the same. I have even tried using Knoppix Live CD to remove the RAID-1 ...
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ThinkServer RD440 raid mess
Does anybody have experience dealing with raid config on these new Thinkpad servers?
My problem is the following: In order to be able boot this server I must put the drives to RAID1 to create an SCM ...
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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_]. ...
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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 ...
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Path of md device wrong after reboot
I have to set up a software raid (level1) on a Ubuntu server 12.04. It should serve files in the network via Samba. The server has the following disks:
250gb Sata hdd (Ubuntu is installed on that ...
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How do I check if smartd and mdadm are running correctly?
I have a raid system on debian:
Disk /dev/sda: 320.1 GB,...
Device Boot Start End Blocks Id System
/dev/sda1 * 1 2432 19535008+ fd Linux raid ...
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Are ext4 RAID5 tuning options useful under LVM?
I'm setting up a system with a system with a mdadm RAID5 which is the sole PV for a VG which hosts 4 LVs.
When I make the filesystem, would the mkfs.ext4 -E option be useful? Or is its effect not ...
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Is it reasonable to make a RAID-1 array with a ram disk and a physical disk to maximize read performance and protect data?
In one of the answers on SO (I forgot which one) I've seen a suggestion to make a RAID-1 array composed of a RAM disk and a physical partition. By adding the physical partition with --write-mostly and ...
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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 ...
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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 ...
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How to diagnose intermittently slow raid data transfer rate?
I have an encrypted RAID6 set up on Centos 5.5. When I transfer a large 10gb file from the raid to my computer it will pause at around 4-5gb and again at 9gb. The data transfer drops from 25mb/sec to &...
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Linux Mdadm + LVM recovery
I recently reinstalled my Ubuntu server with 10.04, and am having trouble reactivating the LVM partition which houses all my non-critical data. /dev/sda, /dev/sdb, /dev/sdc, and /dev/sdd are all ...
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How to check (fsck) a filesystem on a md device (linux/mdadm)
I have a partition lying on a software raid device, /dev/md4
On boot, fsck fails and the partiton cannot be mounted.
Trying to fsck manually, I get an error:
sudo fsck /dev/md4
fsck from util-linux-...
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Migrating on-premise server with RAID1 to EC2
I have an on-premise physical server running Debian 10 that I would like to migrate to AWS EC2. The server storage consists of two 1TB HDD drives on /dev/sda and /dev/sdb that have been set up as a ...
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How to create LVM RAID 1 with 4 disks of 2 different sizes?
I have a system with
2 x 1TB (NVMe SSDs)
2 x 2TB (SATA SSDs)
disks and would like to create a RAID 1 system using all available disks (so I have a 3TB RAID1 system at the end). Unfortunately, most ...
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Does KVM/QEMU support mdadm RAID5 properly?
I'm not able to get anything close to usable performance using a guest file located on a mdadm RAID5 array.
I've believed I optimized all the parameters of the array and filesystem for best R5 ...
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Raid 1 from already initialized disk
I have 4TB disk (A) with data in it. Now I've bought a new 4TB disk (B), and I want to start a RAID1 so that B becomes the mirror of A, without loosing data on A. I'm under linux with mdadm tool.
The ...
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How to stop resync and start rebuild on software raid (mdadm)?
I have RAID6 on 24 drives. The raid was setup with mdadm, so it is a software raid. One of the drives died and the server freezed due to that, so it had to be rebooted using Power Cycle (power off + ...
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Linux; Set RAID5 chunk size to 4kB to match FS block size and physical disk sector size
There are many discussions and websites that explain the process of setting up a Linux software RAID with mdadm with the chunk size of a new RAID as 128kBs or 512Kbs. Serverfault is no exception.
I ...
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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, ...
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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 ...
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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 ...
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Odd mdadm output: --examine shows array state failed, --detail shows everything clean
The setup: 8 disks in a mdadm-managed RAID5 array (/dev/md0, made from /dev/sdc through /dev/sdj). One disk (/dev/sdh) is showing SMART errors (increasing pending sector count) so I'm looking to ...
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Getting Grub2 to recognize a Raid 10 boot/root
I've been trying to get my raid to boot from grub2 for about 2 days now and I don't seem to be getting closer. The problem appears to be that it doesn't recognize my raid at all. It doesn't see (md0) ...
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ext3 format options
I'm creating a ext3 filesystem on top of a software raid5 (md) and I'm wondering what are the best parameters when creating the filesystem (with mkfs.ext3) and while mounting.
RAID5 chunk size is ...
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How is 'mdadm' stopped from doing an auto scan at startup?
Debian 10 VM has no software based RAID config, neither is there any intention of creating a software based (mdadm) RAID array.
mdadm is installed purely as a dependency for cockpit-storaged
mdadm ...
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mdadm raid5 was added as a spare to itself
I have a raid 5 device created with mdadm. I was working on it and long story short, I wanted to type mdadm --manage /dev/md127 -a /dev/sdd, but I accidentally typed mdadm --manage /dev/md127 -a /dev/...
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mdadm not assemble after restart
I have 2 disk with the next structure:
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 3,7T 0 disk
├─sda1 8:1 0 2,7T 0 part
└─sda2 8:2 0 931,5G ...
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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 ...
- 5,651
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RAID-5 array being split on reboot (ubuntu)
I've set up a RAID-5 array on Ubuntu 13.04 (kernel 3.8.0-27-generic) using mdadm - v3.2.5 - 18th May 2012. It appears to work fine and be in high spirits:
$ cat /proc/mdstat
Personalities : [linear]...
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MDADM Rebuilding
I'm currently rebuilding a RAID6 MDADM array from 5 devices to 9.
cat /proc/mdstat:
Personalities : [raid6] [raid5] [raid4]
md0 : active raid6 sde1[0] sdg1[9](F) sdh1[8](F) sdi1[6](F) sdj1[7](F) ...
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flashcache with mdadm and LVM
I am having trouble setting up flashcache on a system with LVM and mdadm, I suspect I am either just missing an obvious step or getting some mapping wrong and hoped someone could point me in the right ...
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Recover mdadm RAID 10 array: listing all as spares
I'm a bad person and haven't backed up my RAID elsewhere. I now have a RAID10 array that won't assemble, and I'm hopeful I can save it. Here's the details:
I have five hard drives set up as RAID10 (...
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mdadm reassemble from spare disk crashed during resync
The server crashed while raid-1 /dev/md2 with /dev/sda3 + /dev/sdb3 was resyncing from /dev/sdb3 to /dev/sda3. sadly, /dev/sdb was lost completely due to a hardware fault.
I'm now left with only /dev/...
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reliably and automatically determine connection path of physical position of HDD from /dev/sdX device file
This is kind of a FAQ, but all the answers I found so far are not suited for full automation, which is what I need. So here it goes again.
In Linux:
Is there a reliable way to resolve the udev ...
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mdadm raid6 recovery reads more from one drive?
I just replaced a fault drive in my raid6-array (consisting of 8 drives) during the recovery I did notice something strange in iostat. All drives are getting the same speeds (as expected) except for ...
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Putting a spare Raid device back to active state
I have a problem with my Raid setup. I have 3 disks in my Raid:
md2 : active raid5 sdc3[3](S) sdb3[4](S) sda3[0]
2925532672 blocks level 5, 64k chunk, algorithm 2 [3/1] [U__]
md1 : active ...
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Can iostat output show mismatched read data for mdadm raid5 array?
I'm trying to understand this iostat output:
tps kB_read/s kB_wrtn/s kB_dscd/s kB_read kB_wrtn kB_dscd Device
500.30 58.9M 19.4k 0.0k 329.1G ...
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Is it OK to prepare drives in mdadm RAID in LinuxMint live and then run CentOS7 installer?
I am planning to setup a CentOS7 server with software RAID. Since the CentOS7 installer isn't particularly good at preparing the disks, I wonder if it would be OK to boot up a LinuxMint 18 live, do ...
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Create mdraid with multipath disks in in RHEL7:
I am still novice in the world of storage. I am working on a project of migrating our backups infra from Solaris to Linux.
As part of that, I have rebuilt a server to Linux (RHEL7) and it has 2 root ...
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Which are possible hierarchies for bcache, mdadm RAID and LVM?
Assuming I want to use bcache for caching, mdadm for RAID (1) and LVM for partitioning (and that I don't care that there might be performance drawbacks due to many levels of I/O and device management ...
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mdadm raid1 back to single drive
I have a raid1 install of debian 7 with software mdadm on 2 disks.
What I want here is to split this to 2 separate systems and be able to multiboot them.
I guess while I have the system running ...
- 31
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syncing mdadm event count
I had a disk die in my level 5 RAID and before I could replace it, my RAID crapped out while I was copying some data onto it.
Reading the RAID kernel wiki on RAID recovery I've tried forcing an ...
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Why mdadm --examine --scan gives two same ARRAYs? [closed]
The following confuses me:
[root@mrak ~]# mdadm --examine --scan
ARRAY /dev/md/0 metadata=1.2 UUID=d3f800db:26de8691:dc0caf45:0f75028b name=mrak.dex.internal:0
ARRAY /dev/md/0 metadata=1.2 UUID=...
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mdadm did not notice a failed disk in raid0
I have a server with mdadm raid0:
# mdadm --version
mdadm - v3.1.4 - 31st August 2010
# uname -a
Linux orkan 2.6.32-5-amd64 #1 SMP Sun Sep 23 10:07:46 UTC 2012 x86_64 GNU/Linux
One of the disk has ...
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