Personnal identity

$ ssh-keygen -lf .ssh/id_ed25519.pub
256 SHA256:0sKI/pBL0PCpSZjM2oj7zVp1sfHK2szemcx8AaxaUyI my_email (ED25519)

My SSH public key is available here. It is not an RSA key, it's ED25519 instead.

Server identities

ed25519 Sha256

(displayed when you establish connection for the first time with the machine)

ed25519 Publickey

(displayed in your "known_hosts" file under the .ssh/ directory)

Tips to manually write your "known_hosts" file

This file is located at ~/.ssh/known_hosts in your home directory. You can edit it to add IPv4 adresses or IPv6 adresses and multiple Domain Names for a single machine. Also you can create separate known_hosts files (for each host for example) and refer to them into your .ssh/config file.

Example:
[nsd.casperlefantom.net]:54444 ssh-ed25519 """Put ed25519 publickey here"""

Onion Routing

You can reach machines using end-to-end Tor Network if you wish.

Just send DNS query to get .onion address of the machine, like this:
$ dig nse.casperlefantom.net TXT +short
"wuvphkytdeukbrqm.onion"