Hey @Giulio Prisco!

I persuaded the room to work by brute-force

that sounds rather extreme now doesn't it ;).

I assume you executed

ufw default deny

Which blocks all traffic through the "uncomplicated firewall" that isn't specifically whitelisted. (if you haven't than that's probably a good idea. it will keep baddies out of postgres/redis/telnet/etc services that you have installed on the machine unless you open those up)

you then executed

ufw allow 8007
ufw allow 8008

to whitelist those specific ports.

Now if you want to white-list http traffic, https traffic as well as SSH access to your server you can simply just:

ufw allow http
ufw allow https
ufw allow ssh

http, https, and ssh are ufw TCP template presets. if you run ssh on another port than 22 (I'd recommended this to make it harder for baddies to get in), then you need to allow that specific port using ufw allow [your-custom-port-number]/tcp (so as an example ufw allow 5001/tcp

You would also do this for all other services you are running on your machine that you'd like to expose.

As soon as you have set all your rules you can type ufw enable or ufw reload to activate or reload ufw with the new configuration.

You can check all your rules (when the firewall is enabled) by executing:

ufw status

Here's a full list and handy guide on how to use the UFW firewall.

https://help.ubuntu.com/community/UFW