

You could spin a publicly exposed WireGuard daemon firewalled to allow peers access to the non-public SSH port only, which would result in double encryption, but would give you the peace of mind that an attacker would have to compromise both at the same time, which is very unlikely. Plus, WireGuard is very cheap to deploy and produces no logs. We use that model in my office to access our server.
Edit: Otherwise, as others mentioned, you’d move the SSH daemon to a random port, disable password login and weaker keys and cyphers, setup Fail2ban, and optionally setup GeoIP blocking (only allow IPs from your region to connect).



Without root user login, the attacker would have to guess not only the password to the user but also the username (hopefully it’s not something simple like admin), and once you are logged in you can use sudo -i to chage into root, which will require a password, therefore, we also disable password login so if someone does manage to somehow compromise the SSH user, they’d still need the password to become root.