How to recover level 1 RAID volume?

picgla

12/22/22, 6:11 PM

One disk in a two-disks level 1 array failed. I added another disk to the array and resynchronization completed successfully. While the synchronization was running, I removed the failed volume and the array filesystem vanished.

So I have two questions:

What happened when I removed the failed array that caused the existing filesystem to vanish?
Is it possible to recover the filesystem on the array?

Current status:

# mdadm -Es
ARRAY /dev/md/2  metadata=1.2 UUID=a58fd446:5acce560:16946592:61a8ef7e name=ckhb02:2

# cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md127 : active raid1 sdf1[2] sdd[0]
      10737418240 blocks super 1.2 [2/2] [UU]
      bitmap: 0/80 pages [0KB], 65536KB chunk

unused devices: <none>

# mdadm --detail /dev/md127
/dev/md127:
           Version : 1.2
     Creation Time : Sun Jun 28 16:55:00 2020
        Raid Level : raid1
        Array Size : 10737418240 (10240.00 GiB 10995.12 GB)
     Used Dev Size : 10737418240 (10240.00 GiB 10995.12 GB)
      Raid Devices : 2
     Total Devices : 2
       Persistence : Superblock is persistent

     Intent Bitmap : Internal

       Update Time : Tue Aug 17 13:20:32 2021
             State : clean
    Active Devices : 2
   Working Devices : 2
    Failed Devices : 0
     Spare Devices : 0

Consistency Policy : bitmap

              Name : ckhb02:2  (local to host ckhb02)
              UUID : a58fd446:5acce560:16946592:61a8ef7e
            Events : 175334

    Number   Major   Minor   RaidDevice State
       0       8       48        0      active sync   /dev/sdd
       2       8       81        1      active sync   /dev/sdf1

/bin/ls -lF /dev/disk/by-uuid yields no volume associated with the array.

0 + 1

raid

mdadm

Terrance

12/22/22, 7:40 PM

"Working Devices : 2 Failed Devices : 0 Spare Devices : 0" Are you sure you replaced the correct drive? Also before rebuilding a RAID1 it is best to clone the partition layout to the new drive. `sudo apt install sgdisk` then `sudo sgdisk /dev/sdf -R /dev/sdd` so that the partition layout of your existing drive (/dev/sdf) is cloned to the new drive (/dev/sdd). Then you rebuild with the command of `sudo mdadm --manage /dev/md127 --add /dev/sdd1`