The other fun thing here, at least with docker-compose, is that it behaves really badly with IPv6, essentially, if you don't manually set a IPv6 address, then a

The other fun thing here, at least with docker-compose, is that it behaves really badly with IPv6, essentially, if you don't manually set a IPv6 address, then all IPv6 to the host address is masqueraded to IPv4, with the visible address being the router address for the network. So, Any external IPv6 connections come in looking like they're from the local network.