Configuring Fluent Bit
Currently, Fluent Bit supports two configuration formats:
Yaml: standard configuration format as of v3.2.
Classic mode: to be deprecated at the end of 2025.
Command line interface
Fluent Bit exposes most of it features through the command line interface. Running the -h option you can get a list of the options available:
$ docker run --rm -it fluent/fluent-bit --help
Usage: /fluent-bit/bin/fluent-bit [OPTION]
Available Options
-b --storage_path=PATH specify a storage buffering path
-c --config=FILE specify an optional configuration file
-d, --daemon run Fluent Bit in background mode
-D, --dry-run dry run
-f, --flush=SECONDS flush timeout in seconds (default: 1)
-C, --custom=CUSTOM enable a custom plugin
-i, --input=INPUT set an input
-F --filter=FILTER set a filter
-m, --match=MATCH set plugin match, same as '-p match=abc'
-o, --output=OUTPUT set an output
-p, --prop="A=B" set plugin configuration property
-R, --parser=FILE specify a parser configuration file
-e, --plugin=FILE load an external plugin (shared lib)
-l, --log_file=FILE write log info to a file
-t, --tag=TAG set plugin tag, same as '-p tag=abc'
-T, --sp-task=SQL define a stream processor task
-v, --verbose increase logging verbosity (default: info)
-w, --workdir set the working directory
-H, --http enable monitoring HTTP server
-P, --port set HTTP server TCP port (default: 2020)
-s, --coro_stack_size set coroutines stack size in bytes (default: 24576)
-q, --quiet quiet mode
-S, --sosreport support report for Enterprise customers
-V, --version show version number
-h, --help print this help
Inputs
cpu CPU Usage
mem Memory Usage
thermal Thermal
kmsg Kernel Log Buffer
proc Check Process health
disk Diskstats
systemd Systemd (Journal) reader
netif Network Interface Usage
docker Docker containers metrics
docker_events Docker events
node_exporter_metrics Node Exporter Metrics (Prometheus Compatible)
fluentbit_metrics Fluent Bit internal metrics
prometheus_scrape Scrape metrics from Prometheus Endpoint
tail Tail files
dummy Generate dummy data
dummy_thread Generate dummy data in a separate thread
head Head Input
health Check TCP server health
http HTTP
collectd collectd input plugin
statsd StatsD input plugin
opentelemetry OpenTelemetry
nginx_metrics Nginx status metrics
serial Serial input
stdin Standard Input
syslog Syslog
tcp TCP
mqtt MQTT, listen for Publish messages
forward Fluentd in-forward
random Random
Filters
alter_size Alter incoming chunk size
aws Add AWS Metadata
checklist Check records and flag them
record_modifier modify record
throttle Throttle messages using sliding window algorithm
type_converter Data type converter
kubernetes Filter to append Kubernetes metadata
modify modify records by applying rules
multiline Concatenate multiline messages
nest nest events by specified field values
parser Parse events
expect Validate expected keys and values
grep grep events by specified field values
rewrite_tag Rewrite records tags
lua Lua Scripting Filter
stdout Filter events to STDOUT
geoip2 add geoip information to records
nightfall scans records for sensitive content
Outputs
azure Send events to Azure HTTP Event Collector
azure_blob Azure Blob Storage
azure_kusto Send events to Kusto (Azure Data Explorer)
bigquery Send events to BigQuery via streaming insert
counter Records counter
datadog Send events to DataDog HTTP Event Collector
es Elasticsearch
exit Exit after a number of flushes (test purposes)
file Generate log file
forward Forward (Fluentd protocol)
http HTTP Output
influxdb InfluxDB Time Series
logdna LogDNA
loki Loki
kafka Kafka
kafka-rest Kafka REST Proxy
nats NATS Server
nrlogs New Relic
null Throws away events
opensearch OpenSearch
plot Generate data file for GNU Plot
pgsql PostgreSQL
skywalking Send logs into log collector on SkyWalking OAP
slack Send events to a Slack channel
splunk Send events to Splunk HTTP Event Collector
stackdriver Send events to Google Stackdriver Logging
stdout Prints events to STDOUT
syslog Syslog
tcp TCP Output
td Treasure Data
flowcounter FlowCounter
gelf GELF Output
websocket Websocket
cloudwatch_logs Send logs to Amazon CloudWatch
kinesis_firehose Send logs to Amazon Kinesis Firehose
kinesis_streams Send logs to Amazon Kinesis Streams
opentelemetry OpenTelemetry
prometheus_exporter Prometheus Exporter
prometheus_remote_write Prometheus remote write
s3 Send to S3Last updated