Starting with VyOS 1.2 a mDNS repeater functionality is provided. Additional information can be obtained from https://en.wikipedia.org/wiki/Multicast_DNS.
Multicast DNS uses the reserved address
220.127.116.11, which is
“administratively scoped” and does not leave the subnet. mDNS repeater
retransmits mDNS packets from one interface to other interfaces. This enables
support for devices using mDNS discovery (like network printers, Apple Airplay,
Chromecast, various IP based home-automation devices etc) across multiple VLANs.
Since the mDNS protocol sends the AA records in the packet itself, the repeater does not need to forge the source address. Instead, the source address is of the interface that repeats the packet.
To enable mDNS repeater you need to configure at least two interfaces so that all incoming mDNS packets from one interface configured here can be re-broadcasted to any other interface(s) configured under this section.
mDNS repeater can be temporarily disabled without deleting the service using
mDNS repeater can be enabled either on IPv4 socket or on IPv6 socket or both to re-broadcast. By default, mDNS repeater will listen on both IPv4 and IPv6.
mDNS repeater can be configured to re-broadcast only specific services. By default, all services are re-broadcasted.
Allow listing additional custom domains to be browsed (in addition to the
local) so that they can be reflected.
You can not run this in a VRRP setup, if multiple mDNS repeaters are launched in a subnet you will experience the mDNS packet storm death!
To listen on both eth0 and eth1 mDNS packets and also repeat packets received on eth0 to eth1 (and vice-versa) use the following commands:
set service mdns repeater interface 'eth0' set service mdns repeater interface 'eth1'
To allow only specific services, for example
(instead of all services) to be re-broadcasted, use the following command:
set service mdns repeater allow-service '_airplay._tcp' set service mdns repeater allow-service '_ipp._tcp'
To allow listing additional custom domain, for example
openthread.thread.home.arpa, so that it can reflected in addition to the
local, use the following command:
set service mdns repeater browse-domain 'openthread.thread.home.arpa'