From 8943fc9f877cbee3301a8261ddd27b4b1f15f174 Mon Sep 17 00:00:00 2001 From: rebortg Date: Mon, 30 Nov 2020 20:53:36 +0100 Subject: arrange services and protocols --- docs/configuration/service/mdns.rst | 44 +++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 docs/configuration/service/mdns.rst (limited to 'docs/configuration/service/mdns.rst') diff --git a/docs/configuration/service/mdns.rst b/docs/configuration/service/mdns.rst new file mode 100644 index 00000000..9d6a292a --- /dev/null +++ b/docs/configuration/service/mdns.rst @@ -0,0 +1,44 @@ +mDNS Repeater +------------- + +Starting with VyOS 1.2 a :abbr:`mDNS (Multicast DNS)` repeater functionality is +provided. Additional information can be obtained from +https://en.wikipedia.org/wiki/Multicast_DNS. + +Multicast DNS uses the 224.0.0.251 address, which is "administratively scoped" +and does not leave the subnet. It retransmits mDNS packets from one interface +to other interfaces. This enables support for e.g. Apple Airplay devices 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. + +Configuration +============= + +.. cfgcmd:: set service mdns repeater interface + + To enable mDNS repeater you need to configure at least two interfaces. To + re-broadcast all incoming mDNS packets from any interface configured here to + any other interface configured under this section. + +.. cfgcmd:: set service mdns repeater disable + + mDNS repeater can be temporarily disabled without deleting the service using + +.. note:: 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! + +Example +======= + +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: + +.. code-block:: none + + set service mdns repeater interface 'eth0' + set service mdns repeater interface 'eth1' + +.. _`Multicast DNS`: https://en.wikipedia.org/wiki/Multicast_DNS -- cgit v1.2.3