Configure UFW on Ubuntu

Installation of UFW:

UFW is already installed on Ubuntu 18.04. You can verify it from here

 which ufw

Output:

root@vps:~#  which ufw
/usr/sbin/ufw

Enable/Disable/Reload UFW:

Enable UFW:

ufw enable

Disable UFW:

ufw disable

Reload UFW:

ufw reload

If you don’t receive output, you need to install UFW. Please refer the following commands.

sudo apt-get install ufw

Allow/Deny port:

Allow port:

ufw allow 80/tcp

Change the port which you want to open.

Deny port:

ufw deny 80

Change the port which you want to deny

Check Status of UFW:

ufw status

Listing Rules:

To list the rules which we have in UFW, run the following command.

ufw status numbered

Output:

root@vps:~# ufw status numbered
Status: active

    To                         Action      From
    --                         ------      ----
[ 1] 80/tcp                     ALLOW IN    Anywhere
[ 2] 80                         DENY IN     Anywhere
[ 3] 80/tcp (v6)                ALLOW IN    Anywhere (v6)
[ 4] 80 (v6)                    DENY IN     Anywhere (v6)

Removing rules:

First, check the status of UFW using the following command.

ufw status numbered

Output:

root@vps:~# ufw status numbered
Status: active

    To                         Action      From
    --                         ------      ----
[ 1] 80/tcp                     ALLOW IN    Anywhere
[ 2] 80                         DENY IN     Anywhere
[ 3] 80/tcp (v6)                ALLOW IN    Anywhere (v6)
[ 4] 80 (v6)                    DENY IN     Anywhere (v6)

This command will show the rules with numbers

Now remove the rule using the following command(Replace the 1 with the rule number which you want to remove)

ufw delete 1

Output:

root@vps:~# ufw delete 1
Deleting:
 allow 80/tcp
Proceed with operation (y|n)? y
Rule deleted
root@vps:~#