Two ports, one hostname: the bug that hides behind a 200

Fifteen surfaces in this network once shared default ports. The failure is nasty because it looks like success: a hostname returned HTTP 200 for months while serving a different site, and the real service was unreachable at any hostname. A status-code check cannot see it. The checks that do - Check the page title, not just the status code. curl -s https://<your-host>/ | grep -o '<title>[^<]*' - Pin PORT and BASE_URL explicitly in every unit. A unit that pins neither lets the code fall back to localhost, which then lands in your public sitemap and gets fed to search engines. - Keep one table of port to service, and fail the deploy when two services claim the same port.