To Check ufw status
#ufw status verbose
Allow and Deny (specific rules)
allow port 53 tcp in your ufw
root@google:# ufw allow 53/tcp
Rule added
root@google:# ufw status
Status: active
To Action From
-- ------ ----
22 ALLOW Anywhere
53/tcp ALLOW Anywhere
remove rule port 53 in your ufw
root@google:# ufw delete allow 53/tcp
Rule deleted
allow 9933 udp
root@google:# ufw allow 9933/udp
Rule added
root@google:# ufw status
Status: active
To Action From
-- ------ ----
22 ALLOW Anywhere
9933/udp ALLOW Anywhere
remove rule port 9933/udp in your ufw
root@google:# ufw delete allow 9933/udp
Rule deleted
deny port 53 in your system
root@google:# ufw deny 53/tcp
Rule added
root@google:# ufw status
Status: active
To Action From
-- ------ ----
22 ALLOW Anywhere
53/tcp DENY Anywhere
remove deny port 53 rule from ufw
root@google:# ufw delete deny 53/tcp
Rule deleted
now we will using ip address / specific ip address
root@google:# sudo ufw allow from 192.168.0.4 to any port 22
Rule added
You have new mail in /var/mail/root
root@google:# ufw status
Status: active
To Action From
-- ------ ----
22 ALLOW Anywhere
22/tcp ALLOW Anywhere
80 ALLOW Anywhere
10050/tcp ALLOW 10.6.0.10
514/udp ALLOW Anywhere
80/tcp ALLOW Anywhere
28778/tcp ALLOW Anywhere
22 ALLOW 192.168.0.4
root@google:# sudo delete ufw allow from 192.168.0.4 to any port 22
sudo: delete: command not found
root@google:# sudo ufw delete allow from 192.168.0.4 to any port 22
Rule deleted
allow icml (ping)
You need to edit /etc/ufw/before.rules and remove the following lines:
# ok icmp codes
-A ufw-before-input -p icmp –icmp-type destination-unreachable -j ACCEPT
-A ufw-before-input -p icmp –icmp-type source-quench -j ACCEPT
-A ufw-before-input -p icmp –icmp-type time-exceeded -j ACCEPT
-A ufw-before-input -p icmp –icmp-type parameter-problem -j ACCEPT
-A ufw-before-input -p icmp –icmp-type echo-request -j ACCEPT
or change the “ACCEPT” to “DROP”
# ok icmp codes
-A ufw-before-input -p icmp –icmp-type destination-unreachable -j DROP
-A ufw-before-input -p icmp –icmp-type source-quench -j DROP
-A ufw-before-input -p icmp –icmp-type time-exceeded -j DROP
-A ufw-before-input -p icmp –icmp-type parameter-problem -j DROP
-A ufw-before-input -p icmp –icmp-type echo-request -j DROP
