The in_udp
Input plugin enables Fluentd to accept UDP payload.
It is included in Fluentd's core.
<source>@type udptag mytag # required<parse>@type regexpexpression /^(?<field1>\d+):(?<field2>\w+)$/</parse>port 20001 # optional. 5160 by defaultbind 0.0.0.0 # optional. 0.0.0.0 by defaultmessage_length_limit 1MB # optional. 4096 bytes by default</source>
Refer to the Configuration File article for the basic structure and syntax of the configuration file.
For <parse>
, refer to Parse Section.
We have observed drastic performance improvements on Linux, with proper kernel parameter settings (e.g. net.core.rmem_max
parameter). If you have high-volume UDP traffic, please make sure to follow Before Installing Fluentd instructions.
​server
​
​parser
​
​extract
​
​compat_parameters
​
See Common Parameters.
The value must be udp
.
type | default | version |
string | required parameter | 0.14.0 |
The tag of the output events.
type | default | version |
integer | 5160 | 0.14.0 |
The port to listen to. (default: 5160
)
type | default | version |
string | 0.0.0.0 (all addresses) | 0.14.0 |
The bind address to listen to.
type | default | version |
string | nil (no adding hostname) | 0.14.10 |
The field name of the client's hostname. If it is set, the client's hostname will be set to its key.
If you set the following configuration:
source_hostname_key client_host
then the client's hostname is set to client_host
field i.e.:
{..."foo": "bar","client_host": "client.hostname.org"}
type | default | version |
string | nil (no adding source address) | 1.4.2 |
The field name for the client's IP address. If you set this option, Fluentd automatically adds the remote address to each data record.
For example, if you have the following configuration:
<source>@type udpsource_address_key client_addr# ...</source>
You will get something like this:
{..."client_addr": "192.168.10.10"...}
type | default | version |
size | 4096 | 0.14.14 |
The maximum number of bytes for the message.
type | default | version |
bool | true | 0.14.23 |
Removes the newline from the end of the incoming payload.
required | multi | version |
true | false | 0.14.10 |
in_tcp
uses the parser plugin to parse the payload.
For more details:
​Parser Plugin Overview​
Here is a Ruby example to send an event to in_udp
:
require 'socket'​us = UDPSocket.opensa = Socket.pack_sockaddr_in(5160, '127.0.0.1')​# This example uses json payload.# In in_udp configuration, need to configure "@type json" in "<parse>"us.send('{"k":"v1"}', 0, sa)us.send('{"k":"v2"}', 0, sa)us.close
If in_udp
gets lots of packets within 1 sec, some packets are dropped. For example, you can see bigger RcvbufErrors
number via netstat -su
.
This means that in_udp
with one process cannot handle such traffic loads. Try multi workers.
If this article is incorrect or outdated, or omits critical information, please let us know. Fluentd is an open-source project under Cloud Native Computing Foundation (CNCF). All components are available under the Apache 2 License.