zlacker

Your understanding is correct, unfortunately. Not only that, the developers are also reluctant to make 127.0.0.1:####:#### the default in their READMEs and docker-compose.yml files because UsEr cOnVeNiEnCe, e.g. https://github.com/louislam/uptime-kuma/pull/3002 closed WONTFIX

>>smarx0+(OP)
Amazing. I just don't know what to say, except that anyone who doesn't know how to open a firewall port has no business running Docker, or trying to understand containerization.

As someone says in that PR, "there are many beginners who are not aware that Docker punches the firewall for them. I know no other software you can install on Ubuntu that does this."

Anyone with a modicum of knowledge can install Docker on Ubuntu -- you don't need to know a thing about ufw or iptables, and you may not even know what they are. I wonder how many machines now have ports exposed to the Internet or some random IoT device as a result of this terrible decision?