How to fix coolify error 'port 80 is in use'

TL;DR it's probably nginx starting automatically.

My coolify instance is running on Ubuntu 24.04 and nginx started automatically for it on boot. This attached the process to port 80, which coolify needs to boot up, although that is considered a bug, and should be fixed in newer (>= 4.0.0-beta.354) versions of coolify

How to fix

Add a systemctl rule to not start nginx automatically.

sudo systemctl disable nginx

Stop the current process from running

sudo systemctl stop nginx

Now try restarting the coolify proxy service.

Caveats

Ofc, if you need the nginx to be running, this won't work for you. You probably don't, if you ended up here 😁

Cheers!