Firewall rule explain

RouterOS General
1

Hello,

I want to want to help me to understand this firewall rule. I see on router example for spammers.
Screenshot from 2017-06-19 13-53-16.png
Somebody can explain more detailed that ?


Regards,

2

It limits the packets on port 25, 587 and 465 (SMTP ports) to no more than 30/min or no more than 30 total connections. Spammers typically directly connect to SMTP servers to send their spam, blacklisting your IP space in the process. Very few users need SMTP access, I would suggest blocking all SMTP ports and whitelisting on customer request (with appropriate rate limit) to protect against malware / botnets etc abusing SMTP ports.

3

I understand that, but I have a mail server on forward connection.

So it is correct that rules ?

Regards,