Service discovery doesn't work without internet

[rolandjitsu]

I'm trying to run the zeroconf server to broadcast on a WiFi network that doesn't have internet, but it doesn't seem to work properly.

As soon as I broadcast on a network that has internet, I can discover the broadcasted server/service.

Is this a known issue?

[probonopd]

Even worse, when not connected to a network, I get:

2019/11/05 20:58:21 Could not determine host IP addresses
Error: process exited with code 1.

which means that my Go program cannot even be launched without internet.

The message seems to be coming from

zeroconf/server.go

Lines 68 to 70 in c2d1b41

	if entry.AddrIPv4 == nil && entry.AddrIPv6 == nil {
	return nil, fmt.Errorf("Could not determine host IP addresses")
	}

This is on Ubuntu 18.04.2 LTS.