Creating SSH Keys

Public key authentication (SSH Key) is a more secure alternative to password authentication that allows users to avoid entering or storing a password, or sending it over the network. Public key authentication uses the client computer to generate the key-pair (a public key and a private key). The public key is then provided to the remote computer's administrator to be installed on that machine.

  1. Create a .ssh directory in your home directory if it does not already exist:
    $ mkdir /home/username/.ssh

    Go to the .ssh folder:

    $ cd /home/username/.ssh
  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.
    The key-pair is generated to your home directory's .ssh folder. For example, assuming you generated the key with the default name id_rsa:

    /home/username/.ssh/id_rsa.pub

    Provide the public key file (for example, id_rsa.pub) to your server administrator so that it can be set up for your server connection.

  4. Use the key in an async session.

    Use the option -i private_key_file, instead of -w password, as in the following example:

    $ async -N TestBackup -d /tmp/dir -r user@server:/tmp/dir -i PATH_TO_THE_PRIVATE_KEY_FILE
    Note: Your private key and public key must be located in the same directory.