Creating SSH Keys (Command Line)

Create a key pair for your computer.

If you are using this machine as a client to connect to other Aspera servers with public key authentication, you can also create key-pairs in command line. Follow these instructions:

Note: You can also use the application GUI to create SSH keys or import existing keys for use with a selected user account. For instructions, see Creating SSH Keys.
  1. Create a .ssh in your home directory if it does not already exist:
    $ mkdir /home/username/.ssh

    Go to the .ssh folder and continue:

  2. Run ssh-keygen to generate an SSH key-pair.

    Run the following command in the .ssh folder. The program prompts you for the key-pair's filename. Press ENTER to use the default name id_rsa. For a passphrase, you can either enter a password, or press return twice to leave it blank:

    $ ssh-keygen -t rsa
  3. Retrieve the public key file.

    When created, the key-pair can be found in your home directory's .ssh folder (assuming you generated the key with the default name id_rsa):


    Provide the public key file (for example, to your server administrator, so that it can be set up for your server connection. The instructions for installing the public key on the server can be found in the Setting Up a User's Public Key; however, the server may be installed on an operating system that is different from the one where your client has been installed.

  4. Start a transfer using public key authentication with the ascp command.

    To transfer files using public key authentication on the command line, use the option -i private_key_file. For example:

    $ ascp -T -l 10M -m 1M  -i ~/.ssh/id_rsa  myfile.txt  jane@

    In this example, you are connecting to the server (, directory /space) with the user account jane and the private key ~/.ssh/id_rsa.