OMV 7 RAID 1 bad HDD replacement

ynlin The OMV docs refer to MD RAID, but you appear to have created a BTRFS filesystem on multiple devices. To confirm this, click on the inverted triangle symbol on the "Storage | Filesystem" WEBUI tab to get the details and post them here between "</>" tags. ( See: [How-To] Post content in a code box ).

Quote from ynlin

Code

<img src="https://forum.openmediavault.org/wsc/index.php?attachment/39221-temp-jpg/&thumbnail=1" class="woltlabAttachment" data-attachment-id="39221" id="wcfImgAttachment0">

[How-To] Post content in a code box - Guides - openmediavault

ynlin

Replacing a disk in a BRTFS RAID1 has to be done via the CLI, not the WebUI. Incidently the replacement disk may be the same size or bigger than the failing/failed drive. The procedure is as follows.

1. Before shutting down your machine, identify the disk to be replaced making a careful note of its serial number as given in the S.M.A.R.T data and/or on the "disk" page of the WebUI.

2. Make a careful note of the serial number of the replacement disk before making the physical swap.

3. Shutdown and make the disk change. (Be aware that when you re-boot the device names of disk may change. e.g. what was /dev/sdc may now have a different letter. This why you need to keep track of disk serial numbers.)

4. When you reboot the OMV machine, I would not expect the BTRFS RAID1 not to mount as it will show the removed device as "missing". You should check this at the CLI with the commands:

btrfs fi sh

findmnt --real -t btrfs

The second command should return nothing. The first command will allow you to work the "devid" of the missing drive.

5. To replace the "missing" device, first mount the BTRFS filesystem in degraded mode at a temporary mountpoint using:

mount /dev/sdX -o degraded /mnt ( X can be any letter from those shown by btrfs fi sh except the missing one)

6. If the mount command succeeds, then carry out the replacement using:

btrfs replace start N  /dev/sdY /mnt ( N must be the device id number of the removed drive which is now missing, Y must be the actual drive letter of the replacement drive which you can identify via its serial number on the WebUI disk list)

7. You can monitor the replacement with:

btrfs replace status /mnt

8. Once complete, unmount the filesystem from its temporary mountpoint and re-mount correctly:

umount /mnt

mount -a

9. Check status of BTRFS filesystem using the WebUI.

Quote from ynlin

Many thanks. It works now.

Glad to here you have it working.