UFW Rule - Deny Routes

Question

I want to deny all outgoing traffic except to a specific address/address range. I attempted:

$ ufw default deny outgoing
$ ufw allow from x.x.x.x to any
$ ufw allow to x.x.x.x from any

However, access to x.x.x.x is denied.

Answer 1

Firstly, you need to check that you're actually using ufw as a firewall component - perform the following:

root@loopback:/home/mn# ufw status
Status: inactive

(Note: This requires root. I strongly recommend using sudo as opposed to root)

The alternative (as you'll see, for me ufw is inactive) is to see if you're running firewalld -sudo firewall-cmd --state should return a value:

root@loopback:/home/mn# firewall-cmd --state 
running

Now,if you're running ufw you can check your rules to see what you have added:

sudo ufw show added       # Show user added rules
more /etc/ufw/user.rules  # Show system rules

To deny all outbound traffic on ufw you would perform the following:

sudo ufw default deny outgoing

Then you set your allow hosts.