Tested on external hard drive Transcend 35T3 (3 TB capacity)
OS: Linux Mint XFCE
Steps:
Install F3 (Test real flash memory capacity)
Open terminal & follow the instruction:
To list all block devices, type (please ignore >>>):
lsblk
After identifying your external device (in this case, the external hdd is /dev/sdb), type:
sudo f3probe --destructive --time-ops /dev/sdb
The whole process was completed in few minutes, however it depends on the capacity & speed of your device.
Hope this helps, cheers.
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