新增以下防火牆條件，即可防止 RouterOS 被掃描 Port！

/ip firewall filter 
add chain=input protocol=tcp psd=21,3s,3,1 action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="Port scanners to list" disabled=no  
add chain=input protocol=tcp tcp-flags=fin,!syn,!rst,!psh,!ack,!urg action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="NMAP FIN Stealth scan" 
add chain=input protocol=tcp tcp-flags=fin,syn action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="SYN/FIN scan" 
add chain=input protocol=tcp tcp-flags=syn,rst action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="SYN/RST scan" 
add chain=input protocol=tcp tcp-flags=fin,psh,urg,!syn,!rst,!ack action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="FIN/PSH/URG scan" 
add chain=input protocol=tcp tcp-flags=fin,syn,rst,psh,ack,urg action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="ALL/ALL scan" 
add chain=input protocol=tcp tcp-flags=!fin,!syn,!rst,!psh,!ack,!urg action=add-src-to-address-list address-list="port scanners" address-list-timeout=14d comment="NMAP NULL scan" 
add chain=input src-address-list="port scanners" action=drop comment="dropping port scanners" disabled=no