Fast and Lightweight Log processor and forwarder for Linux, BSD and OSX
Branch: master
Clone or download
vlad-stoian and edsiper in_exec: add buf_size property for exec plugin (#1116)
* Used head plugin as an example

Signed-off-by: Vlad Stoian <>
Latest commit a398d57 Feb 19, 2019
Type Name Latest commit message Commit time
Failed to load latest commit information.
.github community: add initial Issue Template for Feature Requests and Bug Re… Jul 5, 2018
bin Initial import. Jan 27, 2015
ci ci: add FLB_COVERAGE to calculate test-code coverage, add summary to … Nov 26, 2018
cmake build: set up cmake build procedures for flb_strptime.c Feb 18, 2019
conf out_es: add Logstash_Prefix_Key support (#698) Feb 19, 2019
cpack build: CMake: update package info Mar 14, 2017
debian debian: bump to v1.1.0 Dec 13, 2018
documentation Doc: fix URL Jun 2, 2016
examples compat: include <unistd.h> through monkey/mk_core.h Dec 19, 2018
include pipe: add a portable function to check EAGAIN Feb 18, 2019
init build: fix systemd unit file missing '/' in path when make rpm package ( Dec 5, 2018
lib lib: chunkio: sync windows support changes Feb 8, 2019
plugins in_exec: add buf_size property for exec plugin (#1116) Feb 19, 2019
scripts scripts: test.lua: output table contents (#627) Jun 14, 2018
src pack: gelf: fix wrong warn gelf-level (#912) Feb 19, 2019
tests tests: internal: pack: validate return value of msgpack_unpack_next() Feb 19, 2019
tools/xxd-c tools: xxd-c: include getopt.h through <mk_getopt.h> for portability (#… Jan 17, 2019
.dockerignore dockerfile: switch to distroless as base image for container, add .do… Nov 5, 2018
.gitignore config: new static configuration mode Oct 19, 2018
.travis.yml test: filter_kubernetes: send systemd test message after start (#929) Dec 5, 2018
CMakeLists.txt build: set up cmake build procedures for flb_strptime.c Feb 18, 2019 docs: contributing: fix typo s/pacth or patches/patches (#1049) Jan 25, 2019
Dockerfile dockerfile: bump to v1.1.0 Dec 13, 2018
Dockerfile.debug build: Add Dockerfile.debug to allow 'shell into image' (#1034) Jan 16, 2019 doc: GOLANG: text improvements (#712) Aug 16, 2018
LICENSE Doc: add reference to Apache License v2.0 Jan 28, 2015 Doc: add file May 2, 2017 doc: add travis build badge to (#947) Dec 5, 2018
appveyor.yml CI: Appveyor: disable examples Jan 18, 2017 Debian: add packager script Sep 21, 2015 bitbake: re-work recipe, pull from GIT master Jan 17, 2019
fluentbit_logo.png Doc: Add logo to README Aug 17, 2016
valgrind.supp core: add valgrind suppression error files (dl-open leaks) Sep 22, 2016

Build Status

Fluent Bit is a Data Forwarder for Linux, Embedded Linux, OSX and BSD family operating systems. It's part of the Fluentd Ecosystem. Fluent Bit allows collection of information from different sources, buffering and dispatching them to different outputs such as Fluentd, Elasticsearch, Nats or any HTTP end-point within others. It's fully supported on x86_64, x86 and ARM architectures.

For more details about it capabilities and general features please visit the official documentation:

Quick Start

$ cd build
$ cmake ..
$ make
$ bin/fluent-bit -i cpu -o stdout


Fluent Bit support the following features through plugins:

Input plugins

name option description
CPU cpu gather CPU usage between snapshots of one second. It support multiple cores
Disk disk usage of block device
Dummy dummy generates dummy event
Exec exec executes external program and collects event logs
Forward forward Fluentd forward protocol
Memory mem usage of system memory
MQTT mqtt start a MQTT server and receive publish messages
Netif netif usage of network interface
Kernel Ring Buffer kmsg read Linux Kernel messages, same behavior as the dmesg command line program
Syslog syslog read messages from a syslog daemon
Systemd/Journald systemd read messages from journald, part of the systemd suite
Serial Port serial read from serial port
Standard Input stdin read from the standard input
Head head read first part of files
Health health check health of TCP services
Process proc check health of Process
Random random generate random numbers
Tail tail tail log files
TCP tcp listen for raw JSON map messages over TCP

Filter Plugins

name option description
Record Modifier record_modifier Append/Remove key-value pair
Grep grep Match or exclude specific records by patterns
Nest nest Nest specific records by patterns
Kubernetes kubernetes Enrich logs with Kubernetes Metadata
Stdout stdout Print records to the standard output interface
Parser parser Parse records

Output Plugins

name option description
Counter counter count records
Elasticsearch es flush records to a Elasticsearch server
File file flush records to a file
FlowCounter flowcounter count records and its size
Forward forward flush records to a Fluentd service. On the Fluentd side, it requires an in_forward.
NATS nats flush records to a NATS server
HTTP http flush records to a HTTP end point
InfluxDB influxdb flush records to InfluxDB time series database
Plot plot generate a file for gnuplot
Standard Output stdout prints the records to the standard output stream
Treasure Data td flush records to Treasure Data service (cloud analytics)

Official Documentation

The official documentation of Fluent Bit can be found in the following site:


In order to contribute to the project please refer to the CONTRIBUTING guidelines.


Feel free to join us on our Slack channel, Mailing List or IRC:


This program is under the terms of the Apache License v2.0.


Fluent Bit is made and sponsored by Treasure Data among other contributors.