All Questions
198
questions
0
votes
1
answer
179
views
Mdadm raid 5 array is half the size than expected
I crated a Raid 5 array with mdadm consisting of 4 x 4TB drives, i was expecting the array to be 11-12Tb in total space.
But after building the array I noticed it is actuall half the size of the ...
- 6,455
2
votes
0
answers
445
views
Mayhem with partitions and GPT: mdadm RAID overwritten by Windows partition - possible to fix partition table?
dear Community,
I’m writing as I may have wrecked my system up.
I launched disk manager in Windows; as one of my disks was not recognized, and as Windows kindly suggested me to initialize the-said ...
- 21
5
votes
2
answers
4k
views
Does TRIM avoid the performance impact of mdadm RAID 1 on SSD?
It has already been mentioned in other questions that Red Hat recommends against using mdadm RAID 1 on SSD.
Red Hat also warns that software RAID levels 1, 4, 5, and 6 are not recommended for use ...
- 11
0
votes
1
answer
176
views
Recovering RAID 6: drives are ok, but partitions are "lost"
I faced strange issue with my RAID 6 array (8 HDDs, mdadm). Accidentially 3 drives were disappeared from it, with corresponding result - array has been ruined, but - all 8 drives are perfectly fine, ...
- 101
0
votes
1
answer
443
views
Why MDADM removes disk with no errors from array and marks it as failed
I have a Raid6 that keeps automatically marking a disk (/dev/sdi) as Failed and removing it from the array even though the long test does not show any errors:
Test results
sudo smartctl -l selftest /...
- 121
1
vote
1
answer
297
views
Clean up left-over around a RAID5 coming from a QNAP NAS
I just moved a 12TB RAID5 (4 disks of 4TB) from my QNAP NAS into my Linux Server (/dev/md0), and I noticed that there are three "left-over" partitions on each disk (/dev/sd*1, /dev/sd*2, /...
- 31
1
vote
3
answers
1k
views
Disable warning from mdadm for “degraded” RAID1 with missing drive
I recently had a server outage due to a failed drive. Because of that I set up the server with a new SSD in RAID1 this time but until I managed to get another SSD drive the mdadm-based RAID1 runs with ...
- 845
0
votes
0
answers
131
views
mdadm lost RAID5 after new motherboard and processor
I moved my mdadm RAID5 to a different motherboard/processor, same boot drive.
The array is no longer found during a mdadm --assemble --scan
The motherboard was previously running INTEL RAID, so when ...
- 56
2
votes
0
answers
266
views
Raid6 mdadm reshape operation interrupted - now cannot mount or examine
Edit: Once the reshape finished the drive became fully accessible again.
I had a power failure while a raid6 array was being reshaped, and now certain operations cannot be run against it, including ...
- 279
0
votes
1
answer
2k
views
Remove RAID metadata from HDD so it can be repurposed as a single disk
Previous RAID config was RAID6 in a QNAP NAS, I now want to repurpose the disks as 8 individual disk in different machines.
Each disk appears to have some RAID metadata (superblock) that is stopping ...
- 9,494
1
vote
0
answers
835
views
Restoring/Accessing Synology Raid 1
I was recently asked to try to restore the data from a raid on a synology NAS. The raid consists of 2 disks of 2TB in size. It is a raid 1.
From what I was told, One of the drives has failed and the ...
- 11
3
votes
1
answer
3k
views
Is there a way to show RAID details in a similar way to MDADM?
I find mdadm --detail <device> very useful when I need to know what is going on with the device (/proc/mdadm too).
Example:
/dev/md0:
Version : 1.2
Creation Time : Mon Mar 4 08:35:...
- 287
5
votes
1
answer
538
views
Mount Btrfs raid 5 from failed ReadyNas 104 on Linux - aka how I restore data from my ReadyNas
After about 7 years my ReadyNas finally failed, I would expect from Neatgear detailed recovery instruction, but I read dozens of threads - my problem is not uncommon, but solution was not found.
After ...
1
vote
1
answer
4k
views
Linux MD software raid stripe cache size
From what I can piece together the /sys/block/md0/md/stripe_cache_size is for raid5 and 6 set at a very low default value to avoid starving machines for memory.
By increasing this value you can get a ...
CommunityBot
- 1
2
votes
1
answer
5k
views
Failed raid1, how to add a new disk with mdadm?
I have a home raid1 with 2 disks and one of them just failed (lightning strike on the house). I'm really unfamiliar with mdadm so I'm asking before doing anything stupid.
I can hot-plug a new HD on ...
- 220