Questions tagged [software-raid]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
0 answers
12 views

DRBD-like dirty bitmaps in software-RAID 6

DRBD maintains bitmaps, possibly on a separate device, that record which blocks have been written to after a disconnect. That makes resynchronisation much faster after a temporary disruption because ...
user avatar
  • 405
0 votes
0 answers
16 views

How to handle badblocks on a single drive in a three drive raid0 array

I have three drives in a raid 0 array for speed and have a copy of the data in case the array goes bad. I did a health check on the three discs and found that one of the drives has about 50 read ...
user avatar
  • 1
0 votes
1 answer
43 views

How to configure mdadm.conf properly

I have 2 mdadm arrays. Long time ago, when there was only one raid, i wrote mdadm.conf and it looked like this: # mdadm.conf written out by anaconda MAILADDR root AUTO +imsm +1.x -all ARRAY /dev/md/...
user avatar
  • 167
-2 votes
1 answer
134 views

Is there a GUI to handle LVM and software RAID operations?

Are there any free graphical tools to manage advanced Linux storage schemes such as software RAID and LVM arrays in a similar fashion to how GParted handles partitions? Unfortunately, it seems most ...
user avatar
1 vote
1 answer
38 views

Checking a HDD's health in Raid?

I have a few HDDs in an Ubuntu SW-RAID array, and now I came across to quite a number of questions sticking together: 1.) Is it safe to do smartctl -t (SMART selftest) while the drive is part of an ...
user avatar
  • 207
0 votes
2 answers
26 views

Modifying files on partition mounted both on host and in KVM guest, understanding the caused corruption

I have a server to which I added two SSDs. On the host I created a RAID 1 with both of them by using mdadm. The RAID was created by first creating partitions on the SSDs, and using the partitions to ...
user avatar
  • 571
1 vote
1 answer
155 views

MDADM RAID-1 arrays always do automatic check after booting from a several-day long shutdown

I have multiple PCs with Fedora 35 and RAID-1 MDADM arrays. Among them, only one is facing a weird problem: If I leave it shutdown for more than 2~3 days, it will definitely perform an automatic check ...
user avatar
1 vote
1 answer
40 views

mdadm DegradedArray, is that sofware a problem or hardware defect?

On a dedicated server at the hoster i received the email message for all raid arrays md0/md1/md2 : This is an automatically generated mail message from mdadm running on cn.com > `This is an ...
user avatar
0 votes
0 answers
26 views

Is it possible to have nested striping (besides RAID10) in LVM?

I want to put one RAID on top of other RAIDs. This can easily be done with MDADM by using an existing MD device as one of the members for the new MD device. Similar functionality could probably be ...
user avatar
  • 219
16 votes
3 answers
2k views

How does RAID0 work underneath, when the devices have different sizes?

To my surprise the CentOS 7 installer allowed me to create a RAID0 device consisting of roughly a 17 GB disk and a 26 GB disk. I would've expected that even if it allows that, that the logical size ...
user avatar
  • 679
0 votes
0 answers
22 views

mdadm raid1 arrays different size on same size partitions

I just noticed something very odd. I have two systems with Ubuntu 18.04 Server. They are partitioned exactly the same down to the byte. I verified the partition sizes with blockdev --getsize64. ...
user avatar
2 votes
0 answers
157 views

Mdadm Raid 5 not starting after reboot (IO Error & Dirty Degraded)

I added a new 3TB Drive to my working Raid5 Array yesterday and left it to rebuild overnight. Today I got the following error in journal: Jan 16 07:49:42 iHugo kernel: INFO: task md0_resync:854 ...
user avatar
0 votes
0 answers
33 views

temporary removing device /partition from RAID5 - getting "Device or resource busy"

Here is a current state of my RAID5: And it is rebuilding.... /dev/md10: Version : 1.2 Creation Time : Sun Dec 19 13:28:26 2021 Raid Level : raid5 Array Size : ...
user avatar
  • 137
5 votes
1 answer
240 views

Can a RAID5 disk be moved to a different slot?

I have a healthy RAID5 array with 5 disks: # cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid5 sdb1[6] sdd1[0] sdh1[5] sdf1[2] ...
user avatar
  • 2,968
1 vote
1 answer
69 views

Mismatch in disk size between lsblk and df

I have recently upgraded two soft raid1 2TB disks with a set of two 4TB raid 1 disks. (see Replacing soft RAID1 LUKS disks with larger ones) The guide was amazing, however I find myself with two ...
user avatar
  • 709
0 votes
0 answers
36 views

Duplicated saves with borgbackup

I need to backup data using Borg Backup from a remote server to a local server (raspberry-pi like - it is actually Yunohost) equipped with a 2 slots storage bay. I would like to have identical copies ...
user avatar
  • 1
1 vote
1 answer
126 views

grub2-install throws various errors instead of installing, how to proceed?

The system is CentOS 7. It was installed on two hard disks with MD RAID, one drives died. We decided to switch to two SSDs of just marginally larger size. When they were connected and system was ...
user avatar
0 votes
1 answer
62 views

What is a good way to know mdadm RAID 5 array used size

I run a mdadm RAID 5 array of 4 3TB disks on Ubuntu 18.04, with a total size of 9TB. It displays as a 9.0 TB RAID-5 Array in gnome disk utilities, and the usage is 799 GB free, which means I have over ...
user avatar
  • 103
0 votes
0 answers
28 views

getting command error when setting up RAID5 and cannot recognize 2 HDDs

I am a beginner to programming, but attempting to set up RAID 5. I am following this tutorial: https://www.digitalocean.com/community/tutorials/how-to-create-raid-arrays-with-mdadm-on-ubuntu-16-04 ...
user avatar
2 votes
1 answer
213 views

Using LVM with RAID1

I am using SLES 15 SP3. I need to setup RAID1 with LVM using autoyast.xml In the AutoYast guide, I found examples of how to setup: LVM RAID They seem pretty straightforward and I even tried them and ...
user avatar
  • 121
0 votes
1 answer
503 views

How do I access a Windows Storage Spaces built in Windows 10 on Ubuntu?

Status Update 01/17/22: After 2 months I still have not figured out how to access the storage space from Linux. The kind people over at Superuser didn't seem to know either. There may be a way to do ...
user avatar
  • 1
1 vote
1 answer
805 views

mkfs error: /dev/nvme0n1 apparently in use by the system; will not make a filesystem here

I added a nvme storage device to a Dell 7820 workstation (alias: new-machine). The storage device was used in another server (alias: old-machine) and it seems like it was configured as RAID. Anyway I ...
user avatar
2 votes
0 answers
254 views

in what cases is possible re-adding a disk previously removed with mdadm?

Let's say that I have the following ARRAY: mdadm -Q --detail /dev/md0 /dev/md0: Version : 1.2 Creation Time : Fri Oct 29 17:35:52 2021 Raid Level : raid1 Array Size : ...
user avatar
  • 3,959
1 vote
2 answers
628 views

Slow transfer speed through Samba using software RAID

I have a mini PC (Intel Celeron J4005, 4GB RAM, Intel Gigabit NIC), configured with: Ubuntu (5.4.0-81-generic, installed on sda) Samba (version 4.11.6-Ubuntu) FTP (vsftpd, no encryption) RAID5 (mdadm,...
user avatar
  • 11
0 votes
1 answer
193 views

Why can't I mount a RAID array?

I have a RAID array which seem, if I understand it correctly, to be working correctly: # cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md127 : ...
user avatar
0 votes
0 answers
25 views

RAID5 array is rebuilding after a fresh install of Ubuntu 20.04 Server

I installed Ubuntu 20.04 Server on a system with three Seagate 6TB drives. I have partitioned both sda and sdb in two partitions. The first partition on each disk is of 5G. I combined those two 5G ...
user avatar
  • 516
1 vote
1 answer
352 views

CentOS 8 boots to emergency mode after Raid 1 -> 5 upgrade & power outage

Yesterday I upgraded my CentOS 8 server from a Raid 1, 2 disk setup to a Raid 5, 4 disk setup using mdadm However after the final stage of the upgrade: mdadm --grow /dev/md/pv00 -n 4 and some time ...
user avatar
  • 121
0 votes
0 answers
300 views

How to debug frozen md raid?

We have an old backup server with lots of disks and one mount with md raid 5 setup has now frozen. How to diagnose the problem and get it to running again? I would like to avoid restarting the whole ...
user avatar
0 votes
2 answers
427 views

How to recover Data after "mdadm zero-superblocks"

I wanted to swap from CentOS to Openmediavault. I had a RAID1 with mdadm in place and wanted to split it again into two separate disks. The Guide (Similar to ArchWiki) told me to do the following: ...
user avatar
  • 11
1 vote
0 answers
38 views

Disk drive suddenly restarts and gets removed from the RAID

We have a couple of servers with 6 HDDs in software RAID6. Recently one of the servers has started to experience performance issues and I have noticed that one of the disk drives got removed from the ...
user avatar
4 votes
1 answer
162 views

How should I cope with the 16TiB limit on linux software RAID (md)?

I have used a RAID6 based on partitions on 2TB disks for around 10 years, now. Which I have extended multiple times up to around 12TB by adding disks a few times. With the time, I have progressively ...
user avatar
  • 234
0 votes
1 answer
113 views

Can grub recognize a "degraded" raid1 mdadm partition?

Grub can boot(I have tried) from a zfs "degraded" raid1, is simple: create two zfs pools, one is boot, one is root, each one is raid1...and grub load Linux, with two disk, or with only one ...
user avatar
  • 11k
0 votes
1 answer
71 views

LVM - how to disable scrub --assume-clean

Building a raid10 array with LVM. lvs -a -o name,raid_sync_action,sync_percent reports resync 60.23. Is there a way to disable this scrub like you could do with mdraid by using the --assume-clean ...
user avatar
2 votes
0 answers
169 views

Is there any non-destructive way to change the preferred drive in a raid1 mdadm setup?

I have observed empirically that for a raid1 mdadm array, mostly serving sequential reads from single processes, the first disk is basically always picked. This is also confirmed by this code which ...
user avatar
  • 118
1 vote
1 answer
36 views

Moving a mounted ext4 filesystem between physical disks

Is there a way to move an ext4 filesystem between physical disks transparently for the applications, i.e. while preserving file descriptors? There's no LVM nor hardware RAID, unfortunately. I was ...
user avatar
0 votes
1 answer
258 views

Mixed raid 10 with multiple SSDs and an HDD for redundancy

I currently have a raid 0 array consisting of several SSD drives for increased capacity and to some degree speed. This is set up via mdadm and has worked fine until a drive recently crashed. The array ...
user avatar
  • 3
5 votes
1 answer
580 views

Linux software raid1: What reasons might cause a read speed reduction?

Configuring two PCIe NVMe SSDs as a raid1 Linux software raid instead of boosting read performance has roughly halved the read speed. In similar Linux software raid1 setups (also SSDs) I have seen an ...
user avatar
2 votes
0 answers
115 views

Troubleshooting slow writeback on bcache

can somebody give me a hint, how to troubleshoot bcache in writeback mode? I'm using a RAID 1 (2x500GB SSD) as caching device for the RAID 1 backing device (2x16TB HDD). Dirty data of bcache is not ...
user avatar
  • 21
5 votes
0 answers
296 views

How to fix a bad checksum error on mdadm raid5 array (Ubuntu)

I have a 4 x 4 TB drive configured in a raid5 array. Drives labeled as /dev/sdb1, /dev/sdc1, /dev/sdd1 & /dev/sde1 assembled as /dev/md0 mdadm assemble output When I tried to assemble the array I ...
user avatar
  • 51
0 votes
1 answer
75 views

Is it possible to move non system but data software RAID-1 to different system

I promise I did some research before I ask this question. Still not sure about that. Here is what I am planning to do. I am building a backup server. I am using 2 small HDD software raid-1 for the ...
user avatar
  • 1
1 vote
0 answers
128 views

SoftRaid 3x2TB SATA?

I recently took a new dedicated server ovh whose description is: SoftRaid 3x2TB SATA but I'm not sure I understand the meaning. I suppose there are 3 physical 2TB disks so I would tend to assume it is ...
user avatar
  • 23
6 votes
1 answer
1k views

LVM type raid1 & thinpool is it possible?

We are moving an installation from mdadm raid with LVM on top to pure LVM, so we will add the original raid partitions as indendent partitions to the LVM group Something like: lvcreate -L 240G -n thin ...
user avatar
  • 231
1 vote
0 answers
115 views

Clone excisting main HDD to new raid 1 SSD array

I am currently running Ubuntu server on my main server at my homelab. As for now the main drive that contains everything is just an old 250gb HDD I pulled out from an workstation in 2007. Everything ...
user avatar
  • 111
0 votes
0 answers
477 views

mdadm does not persist RAID when re-booting

I have created a RAID-0 with the following command: mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/disk/by-id/ata-Samsung_SSD_750_EVO_500GB_ABC /dev/disk/by-id/ata-...
user avatar
  • 109
2 votes
1 answer
49 views

bare metal raid array with LVM dissapears after reboot

tl;dr: RAID array + LVM dissapears after reboot. Detail I wanted to set up an encrypted raid array, based on this SO. I set up a RAID array "bare metal" (i.e. on the disks not on the ...
user avatar
  • 187
0 votes
1 answer
438 views

Is it possible to split a single Raid 1 array pair and mount a single disk?

I'm having a lot of problems with raid 1 arrays on my server. Is it possible to split a raid 1 array into two seperate disks, and mount one, or either of them, as regular disks. The raid 1 devices ...
user avatar
2 votes
1 answer
306 views

MDADM RAID1 Creation - Which device is "master"?

In a RAID 1 config with MDADM, which device is the master device during the initialization process? In a RAID 1 config with 2 devices, presumably (?) one device acts as a master and the other as a ...
user avatar
1 vote
1 answer
145 views

MDADM RAID1 creation - What does the initilzation process do?

I am creating a RAID 1 mirror pair with MDADM. After creation of the array sudo mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sda /dev/sdb the array enters an initialization ...
user avatar
4 votes
2 answers
2k views

SSD/NVME friendly MD RAID1 rebuild in Linux

I use SSD and NVME RAID1 arrays to store mostly virtual machine disks. More than 75% of the data are zeros (preallocated images, free space). If a disk fails and gets replaced, the rebuild copies and ...
user avatar
1 vote
0 answers
247 views

How do I set up a software raid when using NVMe drives?

I'm currently trying to set up a software RAID1 on a machine that uses Ubuntu 20.04 with UEFI as the drives are running over NVMe. I've tried to just manually copy the EFI partition over to the second ...
user avatar
  • 11

1
2 3 4 5
7