Configuration files must be flexible enough for any deployment need, but they must keep a clean and readable format.
Fluent Bit Commands extends a configuration file with specific built-in features. The list of commands available as of Fluent Bit 0.12 series are:
Command | Prototype | Description |
---|---|---|
@INCLUDE | @INCLUDE FILE | Include a configuration file |
@SET | @SET KEY=VAL | Set a configuration variable |
Configuring a logging pipeline might lead to an extensive configuration file. In order to maintain a human-readable configuration, it's suggested to split the configuration in multiple files.
The @INCLUDE command allows the configuration reader to include an external configuration file, e.g:
[SERVICE]
Flush 1
@INCLUDE inputs.conf
@INCLUDE outputs.conf
The above example defines the main service configuration file and also include two files to continue the configuration:
[INPUT]
Name cpu
Tag mycpu
[INPUT]
Name tail
Path /var/log/*.log
Tag varlog.*
[OUTPUT]
Name stdout
Match mycpu
[OUTPUT]
Name es
Match varlog.*
Host 127.0.0.1
Port 9200
Logstash_Format On
Note that despites the order of inclusion, Fluent Bit will ALWAYS respect the following order:
- Service
- Inputs
- Filters
- Outputs
Fluent Bit supports configuration variables, one way to expose this variables to Fluent Bit is through setting a Shell environment variable, the other is through the @SET command.
The @SET command can only be used at root level of each line, meaning it cannot be used inside a section, e.g:
@SET my_input=cpu
@SET my_output=stdout
[SERVICE]
Flush 1
[INPUT]
Name ${my_input}
[OUTPUT]
Name ${my_output}