How to block IPs in Ubuntu with ufw

Question

I am trying to block some IPs range that try to login my smtp server. I had done with command

ufw route prepend deny from 45.146.130.0/24
ufw prepend deny from 45.146.130.0/24
ufw deny from 81.30.107.90

But not working they try again and again.

My ufw status is active:

20/tcp                     ALLOW       Anywhere                  
21/tcp                     ALLOW       Anywhere                  
22/tcp                     ALLOW       Anywhere                  
80/tcp                     ALLOW       Anywhere                  
443/tcp                    ALLOW       Anywhere                  
888/tcp                    ALLOW       Anywhere                  
39000:40000/tcp            ALLOW       Anywhere                  
28537/tcp                  ALLOW       Anywhere                  
25/tcp                     ALLOW       Anywhere                  
25/udp                     ALLOW       Anywhere                  
110/tcp                    ALLOW       Anywhere                  
110/udp                    ALLOW       Anywhere                  
143/tcp                    ALLOW       Anywhere                  
143/udp                    ALLOW       Anywhere                  
465/tcp                    ALLOW       Anywhere                  
465/udp                    ALLOW       Anywhere                  
995/tcp                    ALLOW       Anywhere                  
995/udp                    ALLOW       Anywhere                  
993/tcp                    ALLOW       Anywhere                  
993/udp                    ALLOW       Anywhere                  
587/tcp                    ALLOW       Anywhere                  
587/udp                    ALLOW       Anywhere                  
Anywhere                   DENY        193.46.254.0/23           
Anywhere                   DENY        81.30.107.0/24            
Anywhere                   DENY        45.146.130.0/24           
Anywhere                   DENY        81.30.107.0/25            
Anywhere                   DENY        81.30.107.40              
Anywhere                   DENY        81.30.107.24              
Anywhere                   DENY        81.30.107.185             
Anywhere                   DENY        81.30.107.168             
Anywhere                   DENY        81.30.107.90
Anywhere                   DENY FWD    45.146.130.0/24

Anywhere                   DENY FWD    81.30.107.0/24

Anywhere                   DENY FWD    193.46.254.0/23

My logs

2025-05-03T22:41:00.753468+00:00 mail2 postfix/smtpd[183023]: disconnect from azpdsg492br4.stretchoid.com[40.124.173.185] commands=0/0
2025-05-03T22:41:32.761073+00:00 mail2 postfix/smtps/smtpd[180506]: connect from unknown[81.30.107.185]
2025-05-03T22:41:50.494354+00:00 mail2 postfix/smtps/smtpd[180506]: warning: unknown[81.30.107.185]: SASL LOGIN authentication failed: (reason unavailable), sasl_username=terms
2025-05-03T22:41:53.690926+00:00 mail2 postfix/smtps/smtpd[180506]: lost connection after AUTH from unknown[81.30.107.185]
2025-05-03T22:41:53.691023+00:00 mail2 postfix/smtps/smtpd[180506]: disconnect from unknown[81.30.107.185] ehlo=1 auth=0/1 rset=1 commands=2/3
2025-05-03T22:41:55.294642+00:00 mail2 postfix/smtps/smtpd[176868]: connect from unknown[81.30.107.201]
2025-05-03T22:41:57.365304+00:00 mail2 postfix/smtps/smtpd[180506]: connect from unknown[45.146.130.98]

What can I do now?

How to block IPs in Ubuntu with ufw

0 Answers0