Questions tagged [raid5]
The raid5 tag has no usage guidance.
121
questions
0
votes
1
answer
25
views
mdadm RAID5 array became "active, FAILED" and now no longer mounts
Today my RAID5 array status from mdadm --detail /dev/md0 became active, FAILED (I have mobile notifications setup)
Most of the files were present but some were missing. This happened before and I ...
- 111
1
vote
1
answer
89
views
Does RAID always read/write an entire chunk?
Many resources on the internet contain conflicting information regarding read/write logic for RAID chunks.
This answer contains the following (seemingly conflicting) pieces of information:
A 512 KB ...
- 349
4
votes
1
answer
172
views
RAID5 - Mark a disk faulty during reshape
Context
I have a software RAID5 array (mdadm) on 3 disks. Last week, one disk started to get reading issue:
# dmesg
ata3.00: exception Emask 0x0 SAct 0x30000001 SErr 0x0 action 0x0
ata3.00: irq_stat ...
- 43
0
votes
3
answers
101
views
How to extend LVM RAID5
This is the first time I'm posting here; usually, I always find someone who has had the same problem as me. But I'm facing an issue with my RAID5 setup using LVM and could really use some help.
...
- 1
0
votes
1
answer
17
views
raid 5 mdadm replace with read errors
I have a software RAID 5 with 3 disks.
For a few days, sda has been giving errors, and today the new disk arrived.
I launched mdadm --replace and the process started correctly, but due to read errors ...
0
votes
0
answers
25
views
mdraid in weird state after failed rebuild
So my NAS (mdraid level5) mainboard died and I built a new system - there I reassembled the raid and the rebuild started:
md0 : active raid5 sde4[3] sdc4[0] sdd4[2] sdb4[4]
8634123072 blocks level 5,...
1
vote
1
answer
65
views
Trouble Mounting RAID
I have a RAID array that I cannot seem to mount after a power failure. The mount error says it cannot find the UUID even though it is to UUID reported by mdadm.
mdadm --examine --scan
ARRAY /dev/md/0 ...
- 111
0
votes
0
answers
51
views
replace an SSD disk in RAID5 with bigger one
Some years ago I created a RAID5 array with mdadm. It consists of 3 1TB SSD (Samsung SSD 860). Here is how I created it:
mdadm -E /dev/sd[a-c]
fdisk /dev/sda
fdisk /dev/sdb
fdisk /dev/sdc
mdadm -C /...
- 893
-1
votes
1
answer
961
views
What is the difference between BTRFS RAID1 and BTRFS RAID5 on 3+ devices?
According to "Examining btrfs, Linux’s perpetually half-finished filesystem", BTRFS RAID1 is said to be "guaranteed redundancy—copies of all blocks will be saved on two separate devices&...
- 31.8k
1
vote
0
answers
132
views
LVM on RAID 5: LV does not mount at boot, need fsck
I am using Debian 11.
I have a mdadm RAID 5 array of 5 disks (4 active, 1 spare) used as a PV for a VG in which 2 LVs have been created : one for home, one for backup.
The home LV mounts at every boot,...
- 11
0
votes
0
answers
31
views
Missing usable space on RAID5
I have 3 drives, 4TB each, in a RAID5 setup. Usable space is 7.24 TB, all good & checks out. I use 5.5Tb and it reports 600Gb left. Maths does not checkout. I get an external drive and I move 5....
- 101
2
votes
1
answer
4k
views
How do I make a spare device active in a degraded mdadm RAID5
A bit of history to start with. I had a 4 disk RAID5 and one disk failed. I removed it from the array and had it in a degraded state for a while:
mdadm --manage /dev/md127 --fail /dev/sde1 --remove /...
- 23
2
votes
0
answers
209
views
Failed RAID 5 reshape after a sudden reboot
I was running a RAID 5 reshape process (growth from 4 to 5 drives) and at night a cooling fan failed and the server suddenly rebooted itself due to CPU overheat and one drive is now possibly out of ...
- 21
0
votes
1
answer
100
views
Does adding 1 drive to an mdadm RAID5 with SSDs require writing all disks once?
I’m going to build a new storage with a few SSDs in RAID5 under Linux’ mdadm. I am considering buying 5 or 6 SSDs now.
If I add another SSD in the future does adding it to the RAID5 require a full ...
- 548
1
vote
0
answers
42
views
mdadm raid5 error during reshape
I first had a working 3 drive array (3 x 6TB drives) and added a 4th. It added as a spare so i ran the grow command. During this the machine rebooted and it did not recognize the 4th drive when it ...
- 11