This page describes the main configuration file used by Fluent Bit
One of the ways to configure Fluent Bit is using a main configuration file. Fluent Bit allows to use one configuration file which works at a global scope and uses the Format and Schema defined previously.
The main configuration file supports four types of sections:
In addition, it's also possible to split the main configuration file in multiple files using the feature to include external files:
- Include File
The Service section defines global properties of the service, the keys available as of this version are described in the following table:
The following is an example of a SERVICE section:
An INPUT section defines a source (related to an input plugin), here we will describe the base configuration for each INPUT section. Note that each input plugin may add it own configuration keys:
The Name is mandatory and it let Fluent Bit know which input plugin should be loaded. The Tag is mandatory for all plugins except for the input forward plugin (as it provides dynamic tags).
The following is an example of an INPUT section:
A FILTER section defines a filter (related to an filter plugin), here we will describe the base configuration for each FILTER section. Note that each filter plugin may add it own configuration keys:
The Name is mandatory and it let Fluent Bit know which filter plugin should be loaded. The Match or Match_Regex is mandatory for all plugins. If both are specified, Match_Regex takes precedence.
The following is an example of an FILTER section:
Regex log aa
The OUTPUT section specify a destination that certain records should follow after a Tag match. Currently, Fluent Bit can route up to 256 OUTPUT plugins. The configuration support the following keys:
The following is an example of an OUTPUT section:
The following configuration file example demonstrates how to collect CPU metrics and flush the results every five seconds to the standard output:
To avoid complicated long configuration files is better to split specific parts in different files and call them (include) from one main file.
Starting from Fluent Bit 0.12 the new configuration command @INCLUDE has been added and can be used in the following way:
The configuration reader will try to open the path somefile.conf, if not found, it will assume it's a relative path based on the path of the base configuration file, e.g:
- Main configuration file path: /tmp/main.conf
- Included file: somefile.conf
- Fluent Bit will try to open somefile.conf, if it fails it will try /tmp/somefile.conf.
The @INCLUDE command only works at top-left level of the configuration line, it cannot be used inside sections.
Wildcard character (*) is supported to include multiple files, e.g:
Note files matching the wildcard character are included unsorted. If plugins ordering between files need to be preserved, the files should be included explicitly.