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Open ports on UFW (uncomplicated Firewall - Ubuntu)



Open ports on UFW (uncomplicated Firewall - Ubuntu).
I wanted to unblock 5432 port for a PostGre SQL setup.

Here is how you do it.




To check status for firewall
ahmed@ahmed-work-horse:~$ sudo service ufw status
ufw start/running

you can also use this command to check status
ahmed@ahmed-work-horse:~$ sudo ufw status
Status: inactive

ahmed@ahmed-work-horse:~$ sudo ufw status
Status: inactive
ahmed@ahmed-work-horse:~$ sudo ufw enable 
Firewall is active and enabled on system startup


If the status is not stopped/waiting, you can enable it using the below command
ahmed@ahmed-work-horse:~$ sudo ufw enable

To open a port say 5432:
ahmed@ahmed-work-horse:~$ sudo ufw allow 5432

To block/close an opened port:
ahmed@ahmed-work-horse:~$ sudo ufw deny 5432

To remove a rule, use delete followed by the rule:
ahmed@ahmed-work-horse:~$ sudo ufw delete deny 5432



It is also possible to allow access from specific hosts or networks to a port. The following example allows ssh access from host 192.168.0.2 to any ip address on this host:
ahmed@ahmed-work-horse:~$ sudo ufw allow proto tcp from 172.16.167.2 to any port 5432
Rules updated


ahmed@ahmed-work-horse:~$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
5432/tcp                   ALLOW       172.16.167.2

ahmed@ahmed-work-horse:~$

Replace 172.16.167.2 with 172.16.0.0/24 to allow port 5432 access from the entire subnet.

ufw can be disabled by:
ahmed@ahmed-work-horse:~$ sudo ufw disable

Thats it!!!.
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