
[[telemetryd-listener-udp]]
= UDP Listener
:description: Learn how to configure and use the UDP listener in OpenNMS {page-component-title} to open a UDP socket and forward the received packets to a parser.

Use the UDP listener to open a UDP socket and forward the received packets to a parser.

The UDP Listener can support multiple parsers if all of these parsers support protocol detection.
If this is the case, each parser defined for the listener will be asked if it can handle the incoming packet.
The first parser that accepts the packet is then used to parse the packet and dispatch it to its queue.

If the listener defines only a single parser, the packet is directly handed over for parsing.

== Facts

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|===
| Class Name          | `org.opennms.netmgt.telemetry.listeners.UdpListener`
| Supported on Minion | Yes
|===

== Parameters

.Optional listener-specific parameters for the UdpListener
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|===
| Parameter        | Description                                                       | Default
| host           | IP address on which to bind the UDP port.                          | 0.0.0.0
| port           | UDP port number on which to listen.                                | 50000
| maxPacketSize  | Maximum packet size in bytes (anything greater will be truncated). | 8096
|===
