cd /etc/fail2ban/
vi jail.local
Edit the following configuration into it, just like below:
[sshd]
enabled = true
port = ssh
banaction = firewallcmd-ipset
action = %(action_mwl)s
logpath = %(sshd_log)s
maxretry = 3
findtime = 15s
bantime = 1h
Save and close it.
Now apply configuriton:systemctl restart fail2ban
Finally, check banned IP of the sshd::
fail2ban-client status sshd