I have a droplet acting as a file server.

My team and I are looking to setup a DMZ for this droplet to prevent outside access to the droplet.

One person on our team as been trying to envision how we would set this up; but all he can work out is how to do it with a physical server.

We are trying to use digitalocean's firewall's since they are free now.

Can anyone help us plan out how we should do this. If we cannot do a true DMZ, is there a DMZ like set up that we can use?