[comice]

Bad firewalling advice imo. Use ubuntu's ufw. Admittedl, ufw feels more difficult if you already know iptables, but it's way more robust than the example given there.

[phazmatis]

Would it have made this guide longer? If so, you're adding unnecessary complexity for what it essentially a beginner guide (says so in the title).

[comice]

It would have made it shorter, and much simpler. Only iptables nerds will find ufw harder.