K. Passwordless

This chapter will be a short one, but highly important because it saves us a lot of time⏳, not having to always insert your password when SSH-ing to your Raspberry Pi🥧.

• But is it secure?

• Yes, it's a RSA encryption.

• How are we going to do this?

• Simple, we will generate an public key, that our raspberry will know and will use to authenticate our connection. The authentication key must be appended to remove hosts ~/.ssh/authorized_key file.

We have to keep in mind that we will ssh from local-host (in this case my Macbook) to remote-host (Raspberry Pi 4).

A. Generate

I already have a public key, I checked this by moving to .ssh directory and running ls -l. The .ssh file is located in your user directory : /home/username/.ssh.

If you don't have it, we must create a public key on our local-host.

$ ssh-keygen -t rsa -b 4096

Then:

• [Enter key]

• [Enter key]

• [Enter key]

  $ Your public key has been saved in /home/ubuntu/.ssh/id_rsa.pub.

B. Copy

!! Make sure to specify your username when trying to copy the key over, if you have a different user (which you most probably due) it will not work.

$ ssh-copy-id -i ~/.ssh/id_rsa.pub [email protected]

Proof: 💪🏼

---

                                            **Congrats, you're done!**

---

C. Remove

This must be done on our remote-host.

In order to remove an authorization key you can use any text editor and simply edit the authorized_keys file from .ssh directory.

In my example, I used vi* authorized_keys -> i to edit -> delete text of previous installed key -> ESC -> :wq to save and exit.

*If you don't know how to use the text editor, check out this site.

Conclusion

We have learned how to set up a passwordless ssh by using RSA public key generation.

We have also learned how to remove the passwordless login.

If you hit a problem or have feedback (which is highly welcomed) please feel free to get in touch, more details in the footer.