Networking / AV-IT
mDNS / Discovery
01 — Definition
How devices find each other by name on a local network, with no DNS server: mDNS (Bonjour / Avahi). NDI, Dante Controller and a host of control apps lean on it for automatic discovery. But it is link-local multicast (224.0.0.251): it crosses neither subnets nor VLANs without an mDNS reflector/repeater configured on the router.
02 — In the field
NDI sources or Dante devices invisible from another VLAN? mDNS is not crossing the boundary. Either keep discovery-dependent gear on a single subnet, or configure an mDNS reflector on the router. Discovery failing across VLANs is a real troubleshooting classic.
04 — Sources
- RFC 6762 §3 — tout nom en .local. MUST partir vers 224.0.0.251 (FF02::FB en IPv6)