/dev/sdd is apparently in use by the system; will not make a filesystem here!
GParted 0.30.0 --enable-libparted-dmraid --enable-online-resize
Libparted 3.2
Format /dev/sdd as ext4 00:00:01 ( ERROR )
* calibrate /dev/sdd 00:00:00 ( SUCCESS )
path: /dev/sdd (device)
start: 0
end: 15633407
size: 15633408 (7.45 GiB)
* clear old file system signatures in /dev/sdd 00:00:01 ( SUCCESS )
write 512.00 KiB of zeros at byte offset 0 00:00:00 ( SUCCESS )
write 4.00 KiB of zeros at byte offset 67108864 00:00:00 ( SUCCESS )
write 512.00 KiB of zeros at byte offset 8003780608 00:00:00 ( SUCCESS )
write 4.00 KiB of zeros at byte offset 8004239360 00:00:00 ( SUCCESS )
write 8.00 KiB of zeros at byte offset 8004296704 00:00:00 ( SUCCESS )
flush operating system cache of /dev/sdd 00:00:01 ( SUCCESS )
* create new ext4 file system 00:00:00 ( ERROR )
mkfs.ext4 -F -O ^64bit -L '' '/dev/sdd' 00:00:00 ( ERROR )
mke2fs 1.44.1 (24-Mar-2018)
/dev/sdd is apparently in use by the system; will not make a filesystem here!
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Edited by Mike Fleetwood