bind_ip in sharedconfig.ini picks the local IPv4 address every server's
RakNet sockets listen on (auth, chat, master, world, the dashboard's
connection to master), separate from external_ip, the address players
are sent. Empty or 0.0.0.0 keeps listening on all interfaces; localhost
means 127.0.0.1. Anything that isn't an IPv4 address stops the server
with an error, and each server logs what it bound to.
Fixes#225
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
