You will then be asked to choose a save location for the keys.At the command line prompt, type ssh-keygen -t rsa.Launch the mac terminal.app ( /Applications/Utilities/Terminal.app).
Click Connect at the bottom and you should now be connected to Flip without the need of two-factor authentication!. For Logon Type select Key file, enter your username for User, and then browse to the location of your `id_rsa.ppk' file. To the right in the General Tab, Select SFTP for the Protocol and enter the Host as. Open FileZilla and go to File->Site Manager. You should now be logged onto Flip without needing to provide a password OR two-factor authorization. On this screen, Browse to the location of your private key file: id_rsa.ppk. Click Connect->SSH->Auth on the sidebar. In Host Name enter Below in the Saved Sessions field enter flip and click Save. Back in PuTTY, you want to create a Saved Session you have not done so already. In the putty window, type chmod 600 ~/.ssh/authorized_keys You now need to set permissions on the file. Back in the editor on paste the copied public key and save the changes. From the PuTTY Key Generator window copy the key as shown in the image below. Use your favorite command text editor (mine is emacs) to open up ~/.ssh/authorized_keys which should be an empty file. ssh does not exist, execute the command mkdir. This will send a request to your Duo Mobile app which you will need to accept
You will be presented with a Duo two-factor prompt. Using PuTTY, log onto and enter your password when prompted. Save it to the same location as before and name it id_rsa.ppk Save it to a location you will be able to easily find it and name it id_rsa.pub Once the key is generated, you will need to save the public key. Open up PuTTY Key Generator, click "Generate," and follow the on-screen instructions. PuTTY Key Generator - a program to generate ssh private and public keys (download here).