v4.0.11

Next generation Telemetry Agent for Logs, Metrics and Traces.

September 23, 2025

KNOWLEDGE BASE

Release Notes v4.0.11

Fluent Bit is a Fast and Lightweight Data Processor and Forwarder for Linux, BSD, Windows and macOS. We are proud to announce the availability of Fluent Bit v4.0.11.

Below is a detailed list of changes included in this release…

What’s new ?


Core


  • input: private plugins must use global event loop (PR #10944)
  • tls
    • add new invalidation api (PR #10944)
    • openssl: add invalidate session callback (PR #10944)
  • upstream: on destroy conn, invalidate tls if used (PR #10944)luent-bit/pull/10895))
  • processor: internal: tests: Ensure to initialize Winsock2 stack (PR #10944)
  • packaging
    • Alma/Rocky/CentOS 10 [Backport to 4.0] (PR #10944)
    • Debian Trixie build support (PR #10944)

Contributors

On every release, there are many people involved doing contributions to different areas like bug reporting, troubleshooting, documentation and coding, without these contributions from the community, the project won’t be the same and won’t be in the good shape that it is now. So THANK YOU! to everyone who takes part of this journey!

Join us

We want to hear about you, our community is growing, and you can be part of it!, you can contact us at:

Latest Version

New release on March 24, 2026

Fluent Bit v5.0.0 is out!

Check out the Release Notes, read the Updated Documentation or jump directly to the Downloads Section.

We are part of a wide community, no vendor lock-in.