I am new to this. I don't allow ssh logins password based. The hackers fail according to sshd but logwatch lists a list of chinese and russian attempts. I wa

I am new to this. I don't allow ssh logins password based. The hackers fail according to sshd but logwatch lists a list of chinese and russian attempts. I was hoping my firewall would block them. I tried entering a block of ips but some of the same ones are connecting. I don't know what this means: Illegal users from: undef: 20 times 183.60.177.246: 7 times 217.14.134.68: 7 times 219.149.30.170: 6 times