Firewall

Hello everybody.

I keep receiving e-mail about block IP like this:

lfd: (sshd) Failed SSH login from 221.181.185.141 (CN/China/-): 5 in the last 3600 secs - Fri Mar 5 15:09:57 2021
lfd: (sshd) Failed SSH login from 179.112.119.206 (BR/Brazil/179-112-119-206.user.vivozap.com.br): 5 in the last 3600 secs - Fri Mar 5 16:14:05 2021
lfd: (sshd) Failed SSH login from 222.187.222.55 (CN/China/-): 5 in the last 3600 secs - Fri Mar 5 17:57:38 2021   
lfd: (sshd) Failed SSH login from 12.221.85.22 (US/United States/-): 5 in the last 3600 secs - Fri Mar 5 18:03:49 2021   

Is this normal ? Can I stop this ? Or can I change port


thanks

its bruteforce attack by the kid hackers but beware they can be successful if your password is small and dictionary based

Is it possible to stop this by disabling ssh log in shell or changing a port

yes we recommend always to change ssh port

ok thanks I will do that....