Questions tagged [raid1]
RAID 1 or Mirrored RAID uses two or more disks that store the same data.
520 questions
1 vote
0 answers
128 views
LVM missing one PV after accidental commands on RAID1 device
I have a serious issue with one of my Oracle Linux 8 servers in a 4-node rack setup. Each node has an identical LVM + RAID1 layout, but one node is now unbootable after i accidentally ran parted and ...
- 11
1 vote
1 answer
140 views
BTRFS RAID1: puzzled by my benchmarks results
I recently compared the performances of two solutions: 1) a MDADM based RAID 1 with EXT4 on top of it and 2) a RAID 1 BTRFS, since it now appears stable and it is gaining in popularity. Here are the ...
- 145
0 votes
1 answer
54 views
Does MDADM read from stale replica in case the latest replica is unavailable/unreachable?
Consider following sequence: write to location1 on copy 1 succeeds, but fails on copy 2 as per documentation, mdadm raid will respond successfully on 1 successful write Next, copy 1 becomes dead and ...
- 121
1 vote
0 answers
96 views
mdadm: replace RAID1 drive with another of different logical sector size
one of our company's webservers had a hardware failure with /dev/sdb. The drive was replaced and I am currently struggling to find proper information on if a logical sector size matters if the ...
- 11
2 votes
1 answer
163 views
RAID1 NAS drive still reporting No space left on device even after adding new disk
I have an issue with my NAS drive reporting No space left on device. On inspection, I found that mdadm reported the filesystem was degraded due to one of the two disks had failed. I replaced the disk ...
- 131
0 votes
1 answer
317 views
mdadm: Value "/dev/md128" cannot be set as devname. Reason: Not POSIX compatible
I am currently stuck after upgrading mdadm version mdadm --version mdadm - v4.2 - 2021-12-30 - 14 One of my RAID arrays (named md128) failed, and after adding a new drive to resync it I get the ...
- 29
3 votes
0 answers
214 views
Migrating RAID1 to a bigger disk while expanding partitions
I need to move a server mdadm RAID1 setup on a new pair of bigger disks, from 2TB to 4TB. The disks are GPT with 4 partitions: /dev/nvme1n1p1 /dev/md0 biosboot /dev/nvme1n1p2 /dev/md1 swap /dev/...
- 31
0 votes
0 answers
56 views
Two disks in mdadm but one has much higher aqu-sz, await, %util
I have two disks in an mdadm RAID1 array but (at times at least) they seem to be performing very differently from one another: 07:24:53 AM tps rkB/s wkB/s dkB/s areq-sz aqu-sz ...
- 53
0 votes
0 answers
125 views
Can't replace dead disk on mdadm raid1
The previous sdb died in my array, so I replaced it. When I try to add the new disk, I get the following error. I can't even add it as a spare. # mdadm --add /dev/md1 /dev/sdb mdadm: add new device ...
0 votes
0 answers
123 views
Configure raid1 on working linux
I have to create a raid1 software on a working AlmaLinux OS. Server has 2 disks, the first (sda) with OS installed and the second (sdb) empty. What's the right procedure to do that? I was thinking ...
0 votes
1 answer
225 views
Reassemble BTRFS RAID1 array (was created by mkfs.btrfs)
I've got RAID1 array (4 HDD) from old dead system. Need to reassemble that RAID1 array on a new system. Old and dead linux system was installed to one separate HDD (which is unrecoverable dead) and ...
- 101
0 votes
0 answers
316 views
Trying to recover mdadm RAID1
I have a RAID1 array that I wanted to split into two individual drives. /dev/sdb and /dev/sdc were the two drives and there were three individual partitions. /dev/sd[bc]1 /dev/md0 /dev/sd[bc]2 /dev/...
- 1
3 votes
2 answers
281 views
What is the risk of putting a RAID superblock at the end of a device?
I want to set up a RAID 1 array using mdadm to store backups (I'll be using rsnapshot to do the actual backups). I've read that using metadata 0.9 or 1.0 format with RAID 1 is advantageous because ...
- 131
0 votes
0 answers
91 views
Resizing RAID-1 devices after dd clone
I had 2 x 250 GB disks with 3 md devices - raid 1 setup on them. One of them is for /. I dd-cloned those disks to another 2 x 2 TB SSDs. What is the best solution to increase the raid device sizes? &...
- 15
0 votes
1 answer
77 views
Partition unreachable in a HDD which was part of a RAID 1 cluster
I am out of options here because of my lack of knowledge and I seriously need a hand in order to get my data back. Yes, I did the mistake of trusting RAID system too much... Here is what happened: One ...
- 103