I am working on setting up a Dockerized service at my company that will need to be load balanced and behind an IIS reverse proxy (for TLS offloading and multi-homed capabilities). The service itself appears to be working fine (I can access it from my workstation computer directly, or through another server’s IIS reverse-proxying to the Swarm manager server). The issue is that I am unable to access the service from the Swarm manager itself. It is running on 0.0.0.0:8080 and I have tried localhost:8080, 127.0.0.1:8080, and <server's static IP>:8080 to no avail.
I read that published Swarm ports were not available on the loopback adapter prior to Windows Server 2019, but this machine is running the latest 2019 build (Windows Server Version 1809, Build 17763), so I was under the impression that I should be able to access this service on loopback. Ideally we should not have to run IIS on a separate server to reverse-proxy to the containerized service. What gives?