Using netcat for file transfers

Netcat is an efficient tool to transfer files between two servers in the same network. It works across all the platforms (Linux, Mac OS X and Windows). For this post, we will demo a file transfer between Ubuntu linux distro and Mac OS X.

Let's first create a large file using dd tool. If you are not familiar with dd, please go through this post.

Here, we have created 3 files of the same size having same content. Let us now transfer those files to Mac OS.

At the receiving end, open a port using the following command:

# For Mac systems
nc -l [port_no] > [output_file_name]

# For Linux systems
nc -l -p [port_no] > [output_file_name]

Now, run the following command from the sender side to send the file.

nc [destination_ip] [destination_port] < [file_to_be_transferred]

In the above pic, the sender machine is on the left hand side while receiver is on right. You can clearly see that the receiver has received the file of size 1 GB.

Netcat is a great alternative to ssh based tools in transfering files across systems and it works for different architectures.

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