I would like to copy a whole data partition (~100 GB) from a computer to a single file on an external USB drive so that I can copy it back on a new empty data partition of an other computer.
The external drive is 1.5 TB and already contains 1 TB of data which I do not want to lose.
So I would like to be able to specify the
of option of the
dd command as a file onto this disk rather than its
/dev/sdX identifier (which otherwise would overwrite the existing data on it).
How to do that?