I have an external HHD that has somehow been formatted as 'linux-raid' when I look at it in gParted. I have no idea how I have accidentally done this but I guess I misused some new feature of an open source tool I use.
$fdisk -l
Disk /dev/sdc: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: 106X
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 395E65FF-3A23-4DDF-9684-2E2D3DDBC43C
Device Start End Sectors Size Type
/dev/sdc1 2048 7814035455 7814033408 3.7T Linux filesystem
$file -skr /dev/sdc1
/dev/sdc1: Linux rev 1.0 ext4 filesystem data, UUID=c2bc2f29-c0ee-48e1-93c3-7ef1ad743190 (extents) (large files) (huge files)
I have looked at this answer but I want to confirm before trying this as I did not use mdadm directly. I don't know how to even confirm what type of RAID is being used. If RAID 1 perhaps I can use this answer but I know I do not have enough local storage to copy the files across.
I am using arch.