Fluent Bit

Infrastructure & DevOpsApache-2.0

A fast log processor and forwarder.

Latest v5.1.2 · by FluentWritten in CWebsitefluent/fluent-bitRSS

Branches

5.1
v5.1.2
5.0
v5.0.10
4.2
v4.2.8

Release activity

Release activity — 13 releases across 13 days since May 7, 2026. Each cell is one day; darker means more releases that day. Nothing is recorded before May 7, 2026. Older weeks are hidden at this screen width.
JunJulAugSep
SundayNo releases on May 24, 2026No releases on May 31, 2026No releases on Jun 7, 2026No releases on Jun 14, 2026No releases on Jun 21, 2026No releases on Jun 28, 2026No releases on Jul 5, 2026No releases on Jul 12, 2026No releases on Jul 19, 2026No releases on Jul 26, 2026No releases on Aug 2, 2026No releases on Aug 9, 20261 release on Aug 16, 2026No releases on Aug 23, 2026No releases on Aug 30, 2026No releases on Sep 6, 2026
MondayNo releases on May 25, 2026No releases on Jun 1, 2026No releases on Jun 8, 2026No releases on Jun 15, 2026No releases on Jun 22, 2026No releases on Jun 29, 2026No releases on Jul 6, 2026No releases on Jul 13, 2026No releases on Jul 20, 2026No releases on Jul 27, 2026No releases on Aug 3, 2026No releases on Aug 10, 2026No releases on Aug 17, 2026No releases on Aug 24, 2026No releases on Aug 31, 2026No releases on Sep 7, 2026
TuesdayNo releases on May 26, 2026No releases on Jun 2, 2026No releases on Jun 9, 2026No releases on Jun 16, 2026No releases on Jun 23, 2026No releases on Jun 30, 2026No releases on Jul 7, 2026No releases on Jul 14, 2026No releases on Jul 21, 2026No releases on Jul 28, 20261 release on Aug 4, 2026No releases on Aug 11, 2026No releases on Aug 18, 2026No releases on Aug 25, 2026No releases on Sep 1, 2026
WednesdayNo releases on May 27, 20261 release on Jun 3, 2026No releases on Jun 10, 2026No releases on Jun 17, 20261 release on Jun 24, 2026No releases on Jul 1, 2026No releases on Jul 8, 2026No releases on Jul 15, 2026No releases on Jul 22, 2026No releases on Jul 29, 2026No releases on Aug 5, 2026No releases on Aug 12, 2026No releases on Aug 19, 2026No releases on Aug 26, 2026No releases on Sep 2, 2026
ThursdayNo releases on May 28, 2026No releases on Jun 4, 2026No releases on Jun 11, 2026No releases on Jun 18, 2026No releases on Jun 25, 2026No releases on Jul 2, 20261 release on Jul 9, 2026No releases on Jul 16, 2026No releases on Jul 23, 2026No releases on Jul 30, 20261 release on Aug 6, 2026No releases on Aug 13, 2026No releases on Aug 20, 2026No releases on Aug 27, 2026No releases on Sep 3, 2026
FridayNo releases on May 29, 2026No releases on Jun 5, 2026No releases on Jun 12, 2026No releases on Jun 19, 20261 release on Jun 26, 2026No releases on Jul 3, 2026No releases on Jul 10, 2026No releases on Jul 17, 2026No releases on Jul 24, 2026No releases on Jul 31, 2026No releases on Aug 7, 2026No releases on Aug 14, 2026No releases on Aug 21, 2026No releases on Aug 28, 20261 release on Sep 4, 2026
SaturdayNo releases on May 30, 20261 release on Jun 6, 2026No releases on Jun 13, 2026No releases on Jun 20, 2026No releases on Jun 27, 20261 release on Jul 4, 2026No releases on Jul 11, 2026No releases on Jul 18, 2026No releases on Jul 25, 2026No releases on Aug 1, 2026No releases on Aug 8, 2026No releases on Aug 15, 2026No releases on Aug 22, 2026No releases on Aug 29, 20261 release on Sep 5, 2026

13 releases since May 7, 2026

Changelog

What changed from 4 to 5
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13 of 13 releases
v5.1.2Latest

Fluent Bit 5.1.2

Added 11
  • Implement stat and thermal_zone for macOS in in_node_exporter_metrics
  • Add time_key support for the HEC event time in out_splunk
  • Add unify_tag option to buffer all tags into one file in out_gcs
  • Implement parquet compressions in out_gcs
  • Support application default credentials in out_gcs
  • Implement namespace exclude in filter_kubernetes
Changed 4
  • Add 1-hour cut-off for expiring staled metrics in out_prometheus_remote_write
  • Update cmetrics to v2.2.2
  • Build wamrc with LLVM-17
  • Expire metrics for networking in in_node_exporter_metrics
Fixed 15
  • Fix startup abort when log_level set via env and config
  • Plug a SEGV occurrence on macOS in runtime tests
  • Clamp the suppression length to what was written in log
  • Plug a crash path in in_winevtlog
  • Fix crash when all channels are missing and ignore_missing_channels is enabled in in_winevtlog
  • Handle partial succeeded requests in opensearch output task

From Fluent Bit

https://fluentbit.io/announcements/v5.1.2/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.1.1...v5.1.2

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How v5.1.2 went
v5.0.10

Fluent Bit 5.0.10

Added 2
  • Add a capability to adjust log level with error paths in in_node_exporter_metrics
  • Enrich EventData key-value map if enabled in in_winevtlog
Fixed 3
  • Yield downstream read retries to the event loop in TLS
  • Handle empty map even if avro schema defines map type in out_kafka
  • Preserve syscall error details in TLS OpenSSL

From Fluent Bit

https://fluentbit.io/announcements/v5.0.10/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.9...v5.0.10

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How v5.0.10 went
v5.1.1

Fluent Bit 5.1.1

Added 4
  • Support timestamp placeholder in out_file
  • Add auto_extract_timestamp parameter in out_splunk
  • Add hostname as primary field and runtime tests in out_logdna
  • Add config map to the plugin registration in plugin_proxy
Changed 1
  • Display evicted logs on dropping chunks in input_chunk in_storage_backlog
Fixed 9
  • Fix persistent chunks issues without matching routes on hot reloading in in_storage_backlog
  • Address underflow of buffer size on startup in out_s3
  • Ensure alignment of reading dword width in compat
  • Address stale failed tasks on dispatch in engine_dispatch
  • Fix incorrect pointer arithmetic in diskstats metric cache in in_node_exporter_metrics
  • Fix SIMD boundary for JSON string encoding in utils

From Fluent Bit

https://fluentbit.io/announcements/v5.1.1/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.1.0...v5.1.1

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How v5.1.1 went
v5.1.0

Fluent Bit 5.1.0

Added 12
  • Extract skills from memory
  • Add in_gpu_metrics input plugin to handle NVIDIA GPU metrics via NVML
  • Implement in_etw event tracing for Windows input plugin
  • Add capability to adjust log level with error paths in in_node_exporter_metrics
  • Add format=parquet,arrow with selectable page compression codecs to out_s3
  • Handle input, output, filter, and processor plugin aliases
Changed 9
  • Enrich EventData key-value map if enabled in in_winevtlog
  • Upgrade cmetrics library to v2.2.0
  • Upgrade cfl library to v1.0.0
  • Reduce protobuf log allocation churn in opentelemetry
  • Re-architect workers support in downstream
  • Reduce protobuf decode allocation churn in in_opentelemetry
Fixed 12
  • Return not found for invalid endpoint in in_opentelemetry
  • Do not recycle a connection after peer close_notify in OpenSSL TLS
  • Fix incorrectly detected C TLS existence in thread_storage
  • Fix stale byte accounting when multiple frames share a buffer in in_forward
  • Plug 2038 problem on timestamp in log_event_decoder time
  • Plug unsupported shared port issue on Windows in http_server

From Fluent Bit

https://fluentbit.io/announcements/v5.1.0/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.9...v5.1.0

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How v5.1.0 went
v4.2.8

Fluent Bit 4.2.8

Changed 1
  • Enrich EventData key-value map in in_winevtlog if enabled
Fixed 2
  • Fix payload parsing over-reads and null safety in out_stackdriver
  • Handle empty map in out_kafka even if avro schema defines map type

From Fluent Bit

https://fluentbit.io/announcements/v4.2.8/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v4.2.7...v4.2.8

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How v4.2.8 went
v4.2.7

Fluent Bit 4.2.7

Changed 1
  • Upgrade librdkafka to v2.15.0
Fixed 5
  • Validate PING is a msgpack array in check_ping for in_forward
  • Align secure forward handshake and chunk ack with protocol spec in out_forward
  • Read magic number endian-safely in streaming decompressor for gzip
  • Fix 100% CPU hang and connection teardown use-after-free in in_forward
  • Return Splunk HEC auth status codes in in_splunk

From Fluent Bit

https://fluentbit.io/announcements/v4.2.7/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v4.2.6...v4.2.7

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How v4.2.7 went
v5.0.9

Fluent Bit 5.0.9

Added 2
  • Implement user-defined performance counters with PDH in in_windows_exporter_metrics
  • Implement openssl trace in in_ebpf
Changed 6
  • Upgrade librdkafka to v2.15.0
  • Generate mostly monotonic event id for increasing traceability in in_ebpf
  • Align secure forward handshake and chunk ack with protocol spec in out_forward
  • Attach k8s metadata for internal logs in filter_kubernetes
  • Use semver and timestamp suffixes to distinguish branches in workflows
  • Return Splunk HEC auth status codes in in_splunk
Fixed 9
  • Validate PING is a msgpack array in check_ping in in_forward
  • Plug segmentation violation on in_tail
  • Mitigate data loss on multiline in filter_write_tag and in_emitter
  • Plug segmentation violation on not found error in out_cloudwatch_logs
  • Fix multi-worker resource-metadata data race in out_stackdriver
  • Fix payload parsing over-reads and null safety in out_stackdriver

From Fluent Bit

https://fluentbit.io/announcements/v5.0.9/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.8...v5.0.9

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How v5.0.9 went
v4.2.6

Fluent Bit 4.2.6

Added 1
  • Add IANA time_zone support for native timestamps in parser
Changed 1
  • Add file path to error messages in node_exporter_metrics
Fixed 9
  • Fix multiple memory leaks and potential corruption in out_stackdriver
  • Harden token refresh parsing in oauth2
  • Handle conversion rules of windows and IANA tzinfo in time_tz
  • Plug a regex literal crash
  • Plug bitwise glitches on 32bit OSes in in_windows_exporter_metrics
  • Use the correct maximum size of Cyrillic in unicode

From Fluent Bit

https://fluentbit.io/announcements/v4.2.6/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v4.2.5...v4.2.6

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How v4.2.6 went
v5.0.8

Fluent Bit 5.0.8

Added 1
  • Implement sched trace in in_ebpf
Changed 1
  • Upgrade cmetrics to v2.1.5
Fixed 19
  • Plug bitwise glitches on 32bit OSes in in_windows_exporter_metrics
  • Plug a regex literal crash
  • Process type and length of pong strictly in out_forward
  • Use the correct maximum size of Cyrillic in unicode
  • Render unset AnyValue in OTLP JSON in opentelemetry
  • Fix stale chunks handling on limits in storage

From Fluent Bit

https://fluentbit.io/announcements/v5.0.8/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.7...v5.0.8

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How v5.0.8 went
v5.0.7

Fluent Bit 5.0.7

Added 5
  • Support label and namespace mapping in out_chronicle
  • Add IANA time_zone support for native timestamps in parser
  • Support stdin plugin on windows in in_stdin
  • Implement dns trace in in_ebpf
  • Provide options for inactive chunks behavior in out_s3
Changed 3
  • Add 100 MB decompression size limit to zstd
  • Handle conversion rules of windows and IANA tzinfo in time_tz
  • Increase PUT_RECORDS_PAYLOAD_SIZE to 10MB in out_kinesis_streams
Fixed 7
  • Serialize worker teardown in http_server to prevent race conditions
  • Fix libevent crash on connection drop in http_server
  • Fix YAML variant cleanup on parser errors in config_format
  • Handle int64 values correctly in avro
  • Check map size before accessing first entry in in_elasticsearch
  • Fix multiple memory leaks and potential corruption in out_stackdriver
  • Discard checksum corrupt chunks on startup in storage
Security 5
  • Fix OOB reads in framed data parser in snappy
  • Fix OOB read from hardcoded remaining length overhead in in_mqtt
  • Reject parts with length < 4 and fix null-terminator OOB in in_collectd
  • Validate array size before accessing message mode fields in in_forward
  • Fix integer overflow in octet-counting length parser in in_syslog

From Fluent Bit

https://fluentbit.io/announcements/v5.0.7/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.6...v5.0.7

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How v5.0.7 went
v4.2.5

Fluent Bit 4.2.5

Added 3
  • Add support for Ubuntu 26.04
  • Add bash-style default value operator :- for environment variables
  • Support label and namespace mapping in out_chronicle
Fixed 17
  • Replace raw read() with pipe abstraction in input_thread to fix crash
  • Set up proper block size for aws compression arrow
  • Handle bracketed IPv6 addresses in network
  • Address wrong assignments of timezone at midnight in parser
  • Fix issue with missing input alias in routing
  • Plug tag keys failure in out_influxdb
Removed 1
  • Remove promoted known keys from out_logdna

From Fluent Bit

https://fluentbit.io/announcements/v4.2.5/

What's Changed

Full Changelog: https://github.com/fluent/fluent-bit/compare/v4.2.4...v4.2.5

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How v4.2.5 went
v5.0.6

Fluent Bit 5.0.6

Added 3
  • Add bash-style default value operator :- for environment variables
  • Add support for Ubuntu 26.04 in packaging
  • Add total limit size configuration for DLQ in storage
Changed 5
  • Upgrade cfl library to v0.7.1
  • Partition OTLP logs by resource in out_kafka
  • Harden listener and architecture for http_server
  • Spawn internal server in threaded mode for http_server
  • Omit SNI for IP literal hosts in TLS
Fixed 8
  • Fix general issues with sds_cat() usage
  • Handle unpacker allocation failure in in_forward
  • Prevent port binding failures in concurrent OTEL tests
  • Ignore duplicate STOP messages to prevent shutdown spin in engine
  • Plug segmentation fault on termination in out_azure_logs_ingestion
  • Fix file append cleanup on failure in in_tail
  • Reconcile files after missed inotify events in in_tail
  • Fix handling of cfl_sds return buffers after cfl upgrade

From Fluent Bit

https://fluentbit.io/announcements/v5.0.6/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.5...v5.0.6

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How v5.0.6 went
v5.0.5

Fluent Bit 5.0.5

Added 1
  • in_ebpf: implement exec trace
Changed 4
  • in_node_exporter_metrics: skip IPv6 metrics collection when disabled
  • aws: update support for additional regions
  • out_s3: handle otlp JSON format
  • lib: cmetrics: upgrade to v2.1.3
Fixed 8
  • filter_kubernetes: destroy TLS session to prevent SSL object leak
  • filter_kubernetes: make memory growth rigidly on filter k8s
  • filter_log_to_metrics: retry timer metric append
  • crypto: fix build with OPENSSL_NO_ENGINE
  • opentelemetry: preserve otlp log resource grouping
  • filter_kubernetes: destroy upstream and TLS context on happy path exit
  • out_forward: fix retain_metadata_in_forward_mode default value
  • input: fix threaded input conditional routing for logs
Removed 1
  • out_logdna: remove promoted known keys

From Fluent Bit

https://fluentbit.io/announcements/v5.0.5/

What's Changed
New Contributors

Full Changelog: https://github.com/fluent/fluent-bit/compare/v5.0.4...v5.0.5

View originalPermalink
How v5.0.5 went

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