Firewall > mDNS [Enabling mDNS reflection]

What is mDNS?

mDNS (multicast DNS) is a protocol that allows devices on the same local network to discover each other and resolve hostnames without requiring a centralized DNS server. mDNS is commonly used by Apple services (Bonjour, Airprint, Airplay, etc). Windows may also use mDNS to discover network printers, for example.

When should mDNS reflection be enabled?

mDNS reflection is only needed if these types of discovery services are required to cross VLANs. By default, mDNS traffic is restricted to its VLAN. Enabling reflection on 2 or more VLANs will forward mDNS packets between the VLANs, allowing discovery across VLANs.

It is recommended that mDNS reflection is only enabled if absolutely necessary. Enabling mDNS reflection will increase the overall amount of multicast packets seen on the network. These packets will also be sent over the air on Wi-Fi and can cause Wi-Fi congestion depending on the environment.The Switch Insights page can be used to see how much multicast traffic is being sent and received on each port.

Please do not hesitate to contact Meter Support to confirm if enabling mDNS is the correct solution for you.

Enabling mDNS Reflection

To enable mDNS reflection navigate to Firewall > mDNS:

Simply flip ON the toggles you would like to forward mDNS traffic between and click ‘Save’.
To disable forwarding to/from a VLAN simply flip the toggle OFF and click ‘Save’.