# Fluentd

Fluentd: Unified Logging Layer (project under CNCF)

Repository: https://github.com/fluent/fluentd
Canonical: https://ross.abutalabs.com/products/fluentd
Homepage: https://www.fluentd.org
Language: Ruby
License: Apache-2.0
License Family: permissive
Topics: fluentd, logging, data-collector, ruby, cncf
Last push: 2026-08-24T06:57:36+00:00
Link (homepage): https://www.fluentd.org
Link (site_page): https://www.fluentd.org/faqs
Link (site_page): https://docs.fluentd.org/
Link (site_page): https://www.fluentd.org/architecture

## Health v2 (maintenance only)
Score: 92/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 78, longevity 100
- inputs: {"age_days": 5554, "days_push": 9, "days_rel": 69, "gap_med": 61, "n_releases_24m": 10}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 13579, forks 1405 (observed 2026-08-28T04:11:03.569893+00:00)

## What it is
Fluentd is an open-source data collector that unifies log and event collection from many sources and routes them to files, databases, cloud services, and other backends. It is a CNCF graduated project with a pluggable architecture of 500+ community plugins, JSON-based data handling, and buffering for reliability.

## Use cases
- collect and centralize logs from many servers
- ship container and Kubernetes logs to Elasticsearch or S3
- parse and transform application logs into structured JSON
- build a unified logging layer decoupled from backends
- forward logs between systems with buffering and failover
- tail log files and stream them to a data lake

## When to choose
- you need a mature, plugin-rich log collector with many input/output integrations
- you want a CNCF-graduated, widely deployed logging layer for Kubernetes or hybrid infrastructure
- you need buffering, failover, and routing between heterogeneous log sources and sinks

## When to avoid
- you need an extremely lightweight forwarder with minimal memory footprint (consider Fluent Bit)
- you want a pure high-performance pipeline without Ruby runtime overhead
- you need full observability beyond logs, such as metrics and traces (consider OpenTelemetry)

## Facets
- artifact type: service
- maturity: stable
- function: logging, etl, streaming, plugin-system, developer-tools
- domain: monitoring, self-hosted, cloud-computing
- platform: windows, cross-platform, self-hosted, ruby
- tags: log-collector, unified-logging-layer, cncf, data-pipeline, log-forwarding, log-aggregation, devops, data-engineering, linux, macos, docker, kubernetes

## Member repositories
- fluent/fluentd (main) score 92
- fluent/fluentd-kubernetes-daemonset (infra) score 99

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:03.569893+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:13:11.727000+00:00, confidence not recorded.
  - readme: https://github.com/fluent/fluentd (fetched 2026-08-28T04:11:03.569893+00:00, sha 8f43318bbdb6)
  - homepage: https://www.fluentd.org (fetched 2026-08-29T08:07:54.393334+00:00, sha eddf731f45c2)
  - site_page: https://docs.fluentd.org/ (fetched 2026-08-29T08:07:54.405686+00:00, sha 8d47071205a2)
  - site_page: https://www.fluentd.org/faqs (fetched 2026-08-29T08:07:54.403054+00:00, sha 3567110f00a7)
  - site_page: https://www.fluentd.org/architecture (fetched 2026-08-29T08:07:54.407658+00:00, sha 2bd87cc5c4cf)
- Data as of 2026-08-30T08:39:29.467469+00:00.