Questions tagged [raid5]
117 questions
34
votes
3 answers
How to safely replace a not-yet-failed disk in a Linux RAID5 array?
I have a software RAID5 array (Linux md) on 4 disks.
I would like to replace one of the disks with a new one, without putting the array in a degraded state, and if possible, online. How would that be possible?
It's important because I don't want…
Totor
- 19,302
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18
votes
2 answers
How to recover a crashed Linux md RAID5 array?
Some time ago I had a RAID5 system at home. One of the 4 disks failed but after removing and putting it back it seemed to be OK so I started a resync. When it finished I realized, to my horror, that 3 out of 4 disks failed. However I don't belive…
stribika
- 5,374
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8
votes
6 answers
Pros and cons of software Parity-RAID (e.g. RAID5)
I was recently told about some problems concerning Parity-RAIDs without a non-volatile cache. More exspensive HW-controllers do have battery-powered caches to finish write-operations in case of power failure. Now, some people say that such a…
user773568
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5
votes
1 answer
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] sde1[1]
31255166976 blocks super 1.2 level…
mivk
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5
votes
0 answers
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 get:
sudo mdadm --assemble /dev/md0
mdadm: failed to…
Ivo
- 51
- 1
5
votes
3 answers
Add linux md raid write journal to and existing array
I have a raid5 array with quite large disks, so reconstruction is really slow in case of a power outage. Thankfully, there is the --write-journal option for linux md raid. The man page lists the --write-journal option in the For create, build, or…
P.Péter
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4
votes
1 answer
How to create a 3x3TB RAID 5 array without losing data from 2 of the drives?
I currently have 2 3TB HDDs, one that is always almost full, and another with ~200GB free. I would like to purchase an extra 3TB drive and setup a RAID 5 array, but I am concerned about losing the existing data.
I have found that mdadm will be used…
Joseph Duffy
- 143
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4
votes
4 answers
Reassemble mdadm-raid5
A friend of mine has a mdadm-raid5 with 9 disks which does not reassemble anymore.
After having a look at the syslog I found that the disk sdi was kicked from the array:
Jul 6 08:43:25 nasty kernel: [ 12.952194] md: bind
Jul 6 08:43:25…
Biggie
- 243
- 2
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3
votes
1 answer
Restore Hardware RAID5 using 'mdadm'
I have a Hydra LCM RAID device with 4 Bays (4x 2TB Hitachi). I was running it in RAID5 mode since 2010. Last year in May the device was starting giving messages that one drive was degraded and I should replace it. So did I. One month later the…
david
- 131
- 5
3
votes
2 answers
mdcheck_start Service Fails to Start
I've got a brand new Ubuntu 20.04 machine built out which is using a mdadm RAID5 configuration (3x 10TB). The system is throwing an error every time I log in. I can see from systemctl that the mdcheck_start service has failed.
I can also see from…
Game Poop
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3
votes
1 answer
Migrate Single Disk to RAID
I have a home server running Centos 7 that I'm using to host various different servers - a webserver, two Minecraft servers, and a PLEX server. Currently I have a 4TB HDD which serves as the primary storage, housing the OS and all files, and a…
Kara Perrin
- 43
- 4
3
votes
0 answers
How to recover data from synology Raid 5?
My old synology server (cs407s), died. So I'm trying to retrieve the data from the disk. I have tree disks from RAID 5. I tried to mount the disk on computer running grml.
# lsblk
sda 8:0 0 465.8G 0 disk
├─sda1 8:1 0 768.7M 0…
thumes
- 31
- 2
3
votes
1 answer
Migrating from hardware to software RAID
I have an old PCI-X controller running 8 drives in RAID 5. I'd like to dump the controller and go to software RAID under Ubuntu. Is there a way to do this and retain the data from current array?
EDIT: (and a slight tangent) The answers below are…
kolosy
- 133
- 6
3
votes
5 answers
Linking Intel RAID 5 partitions to boot disk
I have a 5-disk Intel RAID 5 along with a 6th boot disk with /, /boot, and swap.
What I was planning to do was mount the Intel RAID partitions (which I've added with fdisk) so that the 6th disk /home, /var, /srv, etc. link to the RAID on the other 5…
BLaZuRE
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3
votes
1 answer
mdadm RAID5 cannot be assembled
Yesterday I wanted to do some maintenance on my server. I shut it down pressing the powerbutton once which works just fine every time.
After the server was still shutting down after 10 minutes I called it a day and forced it off using the…
Flatron
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