A container running its own avahi-daemon collides with the host's on :5353.
Instead publish to the host avahi over its mounted D-Bus socket using avahi-tools
(avahi-publish). Needs apparmor=unconfined (docker-default blocks the D-Bus
publish). Documented host prereqs incl. allow-interfaces for multi-bridge hosts.
Tested: publish reaches host avahi and registers the names; on hosts with many
docker bridges avahi self-collides until restricted to the LAN interface.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Self-contained host-network Avahi container publishes the service names over
mDNS so .local works zero-config for guests (macOS/Linux native, Windows needs
Bonjour). Toggle with ENABLE_MDNS=true + BASE_DOMAIN=*.local; build-stack layers
docker-compose.avahi.yml in and builds the image during --prep. mDNS can't serve
the air-gap upstream spoofs (non-.local) — those still need real DNS.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>