Syslog
Syslog input plugins allows to collect Syslog messages through a Unix socket server (UDP or TCP) or over the network using TCP or UDP.
Configuration Parameters
The plugin supports the following configuration parameters:
Key
Description
Default
Mode
Defines transport protocol mode: unix_udp (UDP over Unix socket), unix_tcp (TCP over Unix socket), tcp or udp
unix_udp
Listen
If Mode is set to tcp or udp, specify the network interface to bind.
0.0.0.0
Port
If Mode is set to tcp or udp, specify the TCP port to listen for incoming connections.
5140
Path
If Mode is set to unix_tcp or unix_udp, set the absolute path to the Unix socket file.
​
Unix_Perm
If Mode is set to unix_tcp or unix_udp, set the permission of the Unix socket file.
0644
Parser
Specify an alternative parser for the message. If Mode is set to tcp or udp then the default parser is syslog-rfc5424 otherwise syslog-rfc3164-local is used. If your syslog messages have fractional seconds set this Parser value to syslog-rfc5424 instead.
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Buffer_Chunk_Size
By default the buffer to store the incoming Syslog messages, do not allocate the maximum memory allowed, instead it allocate memory when is required. The rounds of allocations are set by Buffer_Chunk_Size. If not set, Buffer_Chunk_Size is equal to 32000 bytes (32KB). Read considerations below when using udp or unix_udp mode.
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Buffer_Max_Size
Specify the maximum buffer size to receive a Syslog message. If not set, the default size will be the value of Buffer_Chunk_Size.
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Considerations
- When using Syslog input plugin, Fluent Bit requires access to the parsers.conf file, the path to this file can be specified with the option -R or through the Parsers_File key on the [SERVICE] section (more details below).
- When udp or unix_udp is used, the buffer size to receive messages is configurable only through the Buffer_Chunk_Size option which defaults to 32kb.
Getting Started
In order to receive Syslog messages, you can run the plugin from the command line or through the configuration file:
Command Line
From the command line you can let Fluent Bit listen for Forward messages with the following options:
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$ fluent-bit -R /path/to/parsers.conf -i syslog -p path=/tmp/in_syslog -o stdout
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By default the service will create and listen for Syslog messages on the unix socket /tmp/in_syslog
Configuration File
In your main configuration file append the following Input & Output sections:
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[SERVICE]
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Flush 1
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Log_Level info
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Parsers_File parsers.conf
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​
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[INPUT]
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Name syslog
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Path /tmp/in_syslog
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Buffer_Chunk_Size 32000
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Buffer_Max_Size 64000
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​
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[OUTPUT]
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Name stdout
14
Match *
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Testing
Once Fluent Bit is running, you can send some messages using the logger tool:
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$ logger -u /tmp/in_syslog my_ident my_message
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$ bin/fluent-bit -R ../conf/parsers.conf -i syslog -p path=/tmp/in_syslog -o stdout
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Fluent Bit v1.x.x
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* Copyright (C) 2019-2020 The Fluent Bit Authors
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* Copyright (C) 2015-2018 Treasure Data
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* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
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* https://fluentbit.io
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​
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[2017/03/09 02:23:27] [ info] [engine] started
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[0] syslog.0: [1489047822, {"pri"=>"13", "host"=>"edsiper:", "ident"=>"my_ident", "pid"=>"", "message"=>"my_message"}]
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Recipes
The following content aims to provide configuration examples for different use cases to integrate Fluent Bit and make it listen for Syslog messages from your systems.
Rsyslog to Fluent Bit: Network mode over TCP
Fluent Bit Configuration
Put the following content in your fluent-bit.conf file:
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[SERVICE]
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Flush 1
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Parsers_File parsers.conf
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​
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[INPUT]
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Name syslog
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Parser syslog-rfc3164
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Listen 0.0.0.0
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Port 5140
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Mode tcp
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​
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[OUTPUT]
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Name stdout
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Match *
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then start Fluent Bit.
RSyslog Configuration
Add a new file to your rsyslog config rules called 60-fluent-bit.conf inside the directory /etc/rsyslog.d/ and add the following content:
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action(type="omfwd" Target="127.0.0.1" Port="5140" Protocol="tcp")
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then make sure to restart your rsyslog daemon:
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$ sudo service rsyslog restart
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Rsyslog to Fluent Bit: Unix socket mode over UDP
Fluent Bit Configuration
Put the following content in your fluent-bit.conf file:
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[SERVICE]
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Flush 1
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Parsers_File parsers.conf
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​
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[INPUT]
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Name syslog
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Parser syslog-rfc3164
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Path /tmp/fluent-bit.sock
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Mode unix_udp
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Unix_Perm 0644
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​
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[OUTPUT]
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Name stdout
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Match *
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then start Fluent Bit.
RSyslog Configuration
Add a new file to your rsyslog config rules called 60-fluent-bit.conf inside the directory /etc/rsyslog.d/ and place the following content:
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$ModLoad omuxsock
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$OMUxSockSocket /tmp/fluent-bit.sock
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*.* :omuxsock:
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Make sure that the socket file is readable by rsyslog (tweak the
Unix_Perm option shown above).Last modified 5mo ago