To check the status of my raid on Zentyal File Server (Ubuntu Based) i have done this:
$ sudo cat /proc/mdstat
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10]
md0 : active raid1 sda1[0] sdb1[1]
3906884608 blocks super 1.2 [2/2] [UU]
bitmap: 0/30 pages [0KB], 65536KB chunk
unused devices: <none>
After that I done this:
$ sudo mdadm -D /dev/md0
and got this output:
/dev/md0:
Version : 1.2
Creation Time : Wed Apr 21 13:38:51 2021
Raid Level : raid1
Array Size : 3906884608 (3.64 TiB 4.00 TB)
Used Dev Size : 3906884608 (3.64 TiB 4.00 TB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Intent Bitmap : Internal
Update Time : Mon Dec 29 15:17:29 2025
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Consistency Policy : bitmap
Name : beta:0 (local to host beta)
UUID : c48f8912:a38344b0:7af60abb:170fe4d0
Events : 70848
Number Major Minor RaidDevice State
0 8 1 0 active sync /dev/sda1
1 8 17 1 active sync /dev/sdb1
Which points me to check it even deeper
$ sudo mdadm -E /dev/sda1
Results:
/dev/sda1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : c48f8912:a38344b0:7af60abb:170fe4d0
Name : beta:0 (local to host beta)
Creation Time : Wed Apr 21 13:38:51 2021
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 7813769216 sectors (3.64 TiB 4.00 TB)
Array Size : 3906884608 KiB (3.64 TiB 4.00 TB)
Data Offset : 264192 sectors
Super Offset : 8 sectors
Unused Space : before=264112 sectors, after=0 sectors
State : clean
Device UUID : b3f9004b:c546cc67:1f3de76a:1489687f
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Dec 29 15:17:29 2025
Bad Block Log : 512 entries available at offset 24 sectors
Checksum : 63d43825 - correct
Events : 70848
Device Role : Active device 0
Array State : AA ('A' == active, '.' == missing, 'R' == replacing)
and the second drive
$ sudo mdadm -E /dev/sdb1
Results:
/dev/sdb1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : c48f8912:a38344b0:7af60abb:170fe4d0
Name : beta:0 (local to host beta)
Creation Time : Wed Apr 21 13:38:51 2021
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 7813769216 sectors (3.64 TiB 4.00 TB)
Array Size : 3906884608 KiB (3.64 TiB 4.00 TB)
Data Offset : 264192 sectors
Super Offset : 8 sectors
Unused Space : before=264112 sectors, after=0 sectors
State : clean
Device UUID : 338d1383:62062812:06444fb3:fc1aa8e6
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Dec 29 15:17:29 2025
Bad Block Log : 512 entries available at offset 24 sectors
Checksum : f5ea2412 - correct
Events : 70848
Device Role : Active device 1
Array State : AA ('A' == active, '.' == missing, 'R' == replacing)
Those checks where done because a few years ago after restarting my server - which was running at this time Zentyal v7 - the software raid was broken and I had to reinstall everything and setup from scratch.
In this case - my server run 448 days without restart - after reboot everything was up and running...