How To use Caddy with TrueNAS Apps

This is a How-To use Caddy to serve Docker apps hosted on TrueNAS

Why

• Each TrueNAS Apps lives in its own stack, hence cannot communicate to each other
  • The internal Docker DNS magic doesn't work
  • This blocks Caddy to access other containers web servers

How

• In TrueNAS
  • In Network, create a new network interface with an un-routable alias, like 172.172.172.1/24
  • In Apps, expose ports of each apps to be accessible from Caddy, like 172.172.172.1:30001
• In the Caddyfile of Caddy
  • Use the exposed IP & port