I'm new to the linux world and I've been reading a few tutorials on security. I've seen some questions on StackExchange tackling this subject, but from what I've seen, none of the answers clarified things for me.
I keep seeing them (the tutorials) recommending to disable
root due to various reasons, the most important being the fact that servers with root users are mostly likely to fall, should a brute force attack occur (from my undersanting, a brute force attack means an automated process which repeatedly tries to authenticate with a username / password combo, until it succeeds)
Now, assuming that I disable username/password authentication and only SSH RSA key authentication is enabled (and also assuming that I'm pretty confident with the security of the device where the private key is located, and that I also have a passphrase for that key) what would be the risk of having root enabled?
Assuming that attackers will never get hold of my private key (and the passphrase), what are their option(s) of getting access of the server?