Hi users!
We have released fluent-package v5.0.7. fluent-package is a stable distribution package of Fluentd. (successor of td-agent v4)
This is a maintenance release of v5.0.x LTS series. Bundled Fluentd was updated to 1.16.9.
We recommend upgrading to fluent-package v5.0.7!
With an old gem, it caused an exception after FIPS enabled in OpenSSL. We have updated the bundled openssl gem to 3.3.0 to solve the issue.
There were memory leaks under conditions where exceptions frequently occurred during communication between Elasticsearch and fluent-plugin-elasticsearch. The issue was fixed in fluent-plugin-elasticsearch v5.4.4 and bundled into fluent-package v5.0.7.
Please see the download page.
We plan to ship the next LTS version of fluent-package v5.0.8 on September, 2025. The content of updates are still in T.B.D.
As it was already announced Drop schedule announcement about EOL of Treasure Agent (td-agent) 4, td-agent v4 reached EOL in Dec, 2023.
After reached EOL, td-agent v4.5.3 on Windows was released because there was a crash bug during startup on Windows. It was backported fix from fluent-package v5 as it is critical in some case. Even though this was a exceptional maintenance release, but there is no change to the fact that we already stopped maintaining td-agent v4.
We strongly recommend migrating from td-agent v4 to fluent-package v5 (LTS). See Upgrade to fluent-package v5
We have been posting information about Fluentd in Japanese on @fluentd_jp. We would appreciate it if you followed the X account.
Hi users!
We have released v1.16.9 on 2025-05-14. ChangeLog is here.
This release is a maintenance release of v1.16 series. In this release, we have fixed a critical bug of the previous version, v1.16.8. Please do not use v1.16.8.
This release will be bundled for upcoming fluent-package LTS version v5.0.7!
In the previous version v1.16.8, the Windows service (fluentdwinsvc) accidentally stops after starting without stopping the supervisor and worker processes. This is a critical bug of v1.16.8 for users who use Fluentd as a Windows service.
In this release, we have fixed this bug.
See #4954 for more information.
Enjoy logging!
Hi users!
We have released v1.16.8 on 2025-05-01. ChangeLog is here.
This release is a maintenance release of v1.16 series.
This release will be bundled for upcoming fluent-package LTS version v5.0.7!
In this release, we have fixed a bug that Windows service process will continue running even if the supervisor process is dead due to config error or etc.
With fluentd#4942 fixed, it becomes easier to notice config errors and other issues.
formatter_csv: Fixed memory leakThe caching mechanism introduced for performance optimization was caching threads inappropriately in formatter_csv.
The in_exec plugin creates a thread each time to emit an event.
Then all threads were cached in formatter_csv, causing a memory leak.
With fluentd#4920 fixed, it becomes stable.
For comming Ruby 3.5, we have added a fiddle gem as dependency.
We are enforcing stabilizing CI of Fluentd. It has nothing to do with Fluentd's functionality directly, but it is very important to provide stable version of Fluentd continuously.
Enjoy logging!
Hi users!
We have planned to change what docker image provides.
Currently, we ship Fluentd docker image for Alpine and Debian (armhf, arm64, amd64). But, Alpine image in Fluentd was already marked as deprecated, so we will make things forward.
In the near future, we will drop Alpine image. This decision affects existing Alpine image users.
fluent/fluentd:edge will be changed from Alpine to Debian image
If you still want to use Alpine, keep v1.16 series or v1.18 series. (not recommended though)
It was well known that Alpine has possibility of incompatibility and performance issues in contrast to Debian images. It was a historical reason to provide Alpine images - "In the previous versions, we provided them", so there is no positive reason to continue it.
Not only just dropping Alpine image, we will improve tagging rules:
In previous versions, there was no version-specific tag which would follow internal version bump.
For example, if you want to stick to Fluentd v1.18.0, you can select v1.18.0-1.0, but if internal version was bumped to v1.18.0-1.1 or something, need to update it.
There is edge-debian tag, but it does not stick to a specific Fluentd version because it will automatically update when the next major/minor version is released.
For such a purpose, shorter v1.19 or v1.19.x tag will be available in the future release.
Happy logging!
Hi users!
We have released fluent-package v5.0.6. fluent-package is a stable distribution package of Fluentd. (successor of td-agent v4)
This is a maintenance release of v5.0.x LTS series. Bundled Fluentd was updated to 1.16.7.
We recommend upgrading to fluent-package v5.0.6!
In this release, known Windows issues were fixed.
In the previous versions, there had been a known issue that fluent-package could not keep some registry values when upgrading.
Thus, if you modify Fluentd service (fluentdwinsvc) related registry,
you need to restore your configuration after upgrading.
Since v5.0.6, fluent-package was fixed to keep some registry values during upgrading package.
Here is the target registry which will be kept during upgrading fluent-package:
StartDelayedAutostartfluentdopt (logging path might be modified by users)In most cases, fluent-package user might want to keep fluentdopt because
it stores additional command line option parameters.
In this release, bundled Fluentd v1.16.7 also contains the fixes for Windows.
NoMethodError of --daemon optionSee Fluentd v1.16.7 has been released blog article in details.
Please see the download page.
We plan to ship the next LTS version of fluent-package v5.0.7 on June, 2025. The content of updates are still in T.B.D.
As it was already announced Drop schedule announcement about EOL of Treasure Agent (td-agent) 4, td-agent v4 reached EOL in Dec, 2023.
After reached EOL, td-agent v4.5.3 on Windows was released because there was a crash bug during startup on Windows. It was backported fix from fluent-package v5 as it is critical in some case. Even though this was a exceptional maintenance release, but there is no change to the fact that we already stopped maintaining td-agent v4.
We strongly recommend migrating from td-agent v4 to fluent-package v5 (LTS). See Upgrade to fluent-package v5
Hi users!
We have released v1.16.7 on 2025-01-29. ChangeLog is here.
This release is a maintenance release of v1.16 series. In this release, some bugs which are related on Windows were fixed with backporting from v1.18.x.
This release will be bundled for upcoming fluent-package LTS version v5.0.6!
In this release, we have fixed a bug that it will fail when --daemon option is used on Windows.
It was a regression bug since v1.16.0 on Windows, but usually running as a service is recommended way on Windows, so most of Fluentd users were not affected.
In this release, we have fixed the following bugs which are related to start/stop the Fluentd service.
These bug were caused because stop event was not handled correctly in the previous releases.
Typically, this bug will happen if you stop the Fluentd service immediately after startup. Then it could leave the processes or stopping service sometimes can not be completed forever.
We also enforcing stabilizing CI of Fluentd. It has nothing to do with Fluentd's functionality directly, but it is very important to provide stable version of Fluentd continuously.
Not only Windows: Add workaround for unexpected exception #4747, many CI improvements was merged into master, then backported to v1.16 branch, too.
Enjoy logging!
Hi users!
We have released fluent-package v5.2.0. fluent-package is a stable distribution package of Fluentd. (successor of td-agent v4)
This release is a new release of v5.2 series.
GEM_HOME/GEM_PATH in fluentd.batPreviously, when upgrading the fluent-package, you had to stop the fluentd service, install the new version of the fluent-package, then install any necessary plugins, and finally restart the fluentd service.
Starting from fluent-package v5.2.0, we have introduced the zero-downtime restart feature that automatically installs the required plugins during the upgrade process and allows you to upgrade Fluentd without interrupting the logging service.
Please refer to "Advisory for upgrading with zero-downtime".
In the previous versions of msgpack gem, there was a possibility that cause DoS (Denial Of Service) when crafted message was sent to Fluentd.
When that message was sent, it might cause "NoMemoryError" on Fluentd because there is a case that msgpack try to pre-allocate huge amount of memories.
Above behavior was fixed not to pre-allocate over 32k entries (limit pre-allocated amount of memories) in msgpack 1.7.3 and bundled.
GEM_HOME/GEM_PATH in fluentd.batIn the previous versions, fluentd.bat doesn't set GEMHOME/GEMPATH explicitly.
If users set custom GEM_HOME / GEM_PATH environment variables, the
batch file will not work as expected. Therefore, this patch will set
the appropriate values in the batch file.
We have changed so that Fluentd does not restart when the needrestart package is installed.
fluent-package v5.2.0 places /etc/needrestart/conf.d/50-fluent-package.conf.
In this release, the bundled fluent-plugin-systemd was updated to 1.1.0. That release fixed SIGABORT error with inconsistency of memory allocator handling.
The zero-downtime restart feature can be configured by FLUENT_PACKAGE_SERVICE_RESTART environment variable.
Please refer to following section for more details.
FLUENT_PACKAGE_SERVICE_RESTART environmental variable
FLUENT_PACKAGE_SERVICE_RESTART environment variable.FLUENT_PACKAGE_SERVICE_RESTART environmental variableWe have introduced FLUENT_PACKAGE_SERVICE_RESTART environment variable to configure the zero-downtime restart feature.
The variable exists in the following file:
/etc/sysconfig/fluentd/etc/default/fluentdExample:
FLUENT_PACKAGE_OPTIONS=""
# Control method to upgrade service (auto/manual) restart
FLUENT_PACKAGE_SERVICE_RESTART=auto
The service automatically restarts with zero-downtime restart feature when all of the following conditions are met:
The plugins will be automatically reinstalled if needed if your environment has an active online connection. For more details, please refer to "Automate Plugin Install for Update on Demand".
You can use this approach if you prefer to manage plugins manually or if your environment does not have offline connection. If the service was active before the update, it will not restart automatically with this configuration. You need to restart the service manually.
SIGUSR2 signal to the supervisor process, such as with kill -USR2 <PID>systemctl restart fluentd.If you prefer to manage plugins automatically, please set FLUENT_PACKAGE_SERVICE_RESTART to auto (default).
When the service restarts automatically using the zero-downtime restart feature, any missing plugins are automatically detected and reinstalled before the restart.
Previously, automatic restarts after updates were not recommended due to potential issues. If you manually install plugins, you need to reinstall them before restarting when the embedded Ruby version is updated.
To address this, this feature enables automatic plugin installation during the restart process. The steps are as follows:
fluent-plugin- prefix.If you prefer to manage plugins manually, please set FLUENT_PACKAGE_SERVICE_RESTART to manual.
This is useful in cases such as:
In this mode, automatic plugin installation and restarts are disabled.
You can manually install plugins and send a SIGUSR2 signal to trigger the zero-downtime restart feature after the update.
If you use a custom unit file, such as /etc/systemd/system/fluentd.service, please remove these 2 lines.
Environment=GEM_HOME=/opt/fluentd/lib/ruby/gems/...
Environment=GEM_PATH=/opt/fluentd/lib/ruby/gems/...
We don't need GEM_HOME and GEM_PATH.
They will be removed after v5.2.0, but if you use a custom unit file, you need to remove them manually.
If these variables are set, the zero-downtime restart feature may not work correctly.
It is because the new process inherits the original environment variables if using this feature.
Please refer to #713 for more details.
Please see the download page.
We plan to ship the next LTS version of fluent-package v5.0.6 on March, 2025. The content of updates are still in T.B.D.
As it was already announced Drop schedule announcement about EOL of Treasure Agent (td-agent) 4, td-agent v4 was reached EOL in Dec, 2023.
After reached EOL, td-agent v4.5.3 on Windows was released because there was a crash bug during startup on Windows. It was backported fix from fluent-package v5 as it is critical in some case. Even though this was a exceptional maintenance release, but there is no change to the fact that we already stopped maintaining td-agent v4.
We strongly recommend migrating from td-agent v4 to fluent-package v5 (LTS). See Upgrade to fluent-package v5
Hi users!
We have released v1.18.0 on 2024-11-29. ChangeLog is here.
This release is a new release of v1.18 series. In this release, we added zero-downtime-restart as a key feature, enhanced some features and fixed bugs.
In this release, we have added the feature to update the Fluentd process with zero downtime for Linux and macOS environments (not supported on Windows). You can use this feature to reload config and restart Fluentd gracefully.
You can use this feature by sending a SIGUSR2 signal to the supervisor process,
and this changes behavior SIGUSR2 from graceful reload to zero-downtime-restart feature on Linux and macOS environments.
You can still use the conventional graceful reloading feature by directly sending SIGUSR2 to each worker process or using the RPC feature.
However, it had some limitations and issues (Please see #4624 for details).
So, we recommend using this new feature for graceful reloading/restarting unless there is a particular reason.
Please see #4624 for more information.
This feature has been added to support the zero-downtime-restart feature that it launches Fluentd with input plugins only.
This feature has added --with-source-only option in fluentd command, with_source_only option in system configuration and out_buffer plugin which can be used for buffering and relabeling events.
These are used internally to support zero-downtime-restart.
Please see #4661 for more information.
The Embedded Ruby Code has been supported in configuration. In this release, we have extended the syntax to allow the use of Embedded Ruby Code in Hashes and Arrays.
Example:
key1 ["foo","#{1 + 1}"] # Embedded Ruby Code in Array syntax
key2 {"foo":"#{1 + 1}"} # Embedded Ruby Code in Hash syntax
Result:
key1 ["foo","2"]
key2 {"foo":"2"}
Please note that this is not backward compatible, although we assume that this will never affect to actual existing configs.
In case the behavior changes unintentionally, you can disable this feature by surrounding the entire value with single quotes.
Example:
key '{"foo":"#{1 + 1}"}'
SSL_VERIFY_NONE by defaultWe have changed the flags to SSL_VERIFY_NONE by default for server the certification verification.
In the previous versions, it had been necessary to set client_cert_auth false and insecure true to apply SSLVERIFYNONE.
This was an inappropriate combination of settings.
In this release, it can make it possible to apply SSL_VERIFY_NONE with just client_cert_auth false (default).
ensure_fips option to ensure FIPS compliant modeWe have added ensure_fips option in transport section in config to check FIPS mode.
When it configures ensure_fips true, it will check FIPS mode is supported in your environment, if not, just aborts.
By default, it has disabled.
Example:
<transport tls>
ensure_fips true
</transport>
Please see the document for more information.
receive_buffer_size parameter in transport sectionIn the previous versions, the receive_buffer_size option can be set by in_udp only.
In this release, we have added the receive_buffer_size option into transport section too to configure the buffer size on in_tcp or in_syslog plugins.
Example:
<transport udp>
receive_buffer_size 4194304
</transport>
In the previous versions, there was a restriction that only the first record could be handled when the parsed result was multiple records. In this release, we have removed this limitation to handle multiple records appropriately.
You can read more about this limitation in the Remaining problem: filter_parser in Fluentd v1.17.0 release blog.
add_tag_prefix optionWe have added add_tag_prefix option in in_http plugin to add the prefix to the incoming event's tag, similar to in_forward plugin.
Example:
<source>
@type http
add_tag_prefix prod
</source>
We have added path option to log section of system configuration.
Example:
<system>
<log>
path /path/to/log_file
</log>
</system>
We have fixed a NoMethodError when launches fluentd with --daemon command line option under Windows platform.
We have fixed --plugin command line option that it does not overwrite the default value.
Enjoy logging!
Hi users!
We have released fluent-package v5.0.5. fluent-package is a stable distribution package of Fluentd. (successor of td-agent v4)
This is a maintenance release of v5.0.x LTS series. As bundled Ruby was updated to 3.2.6 and Fluentd was updated to 1.16.6. We recommend upgrading to fluent-package v5.0.5!
In this release, focused on updating bundled ones.
GEM_HOME/GEM_PATH in fluentd.batIn the previous versions of msgpack gem, there was a possibility that cause DoS (Denial Of Service) when crafted message was sent to Fluentd.
When that message was sent, it might cause "NoMemoryError" on Fluentd because there is a case that msgpack try to pre-allocate huge amount of memories.
Above behavior was fixed not to pre-allocate over 32k entries (limit pre-allocated amount of memories) in msgpack 1.7.3 and bundled into fluent-package v5.0.5.
GEM_HOME/GEM_PATH in fluentd.batIn the previous versions, fluentd.bat doesn't set GEMHOME/GEMPATH explicitly.
If users set custom GEM_HOME / GEM_PATH environment variables, the
batch file will not work as expected. Therefore, this patch will set
the appropriate values in the batch file.
Above bug was also fixed in fluent-package v5.0.5.
In this release, the bundled fluent-plugin-systemd was updated to 1.1.0. That release fixed SIGABORT error with inconsistency of memory allocator handling.
Please see the download page.
We plan to ship the next LTS version of fluent-package v5.0.6 on March, 2025. The content of updates are still in T.B.D.
As it was already announced Drop schedule announcement about EOL of Treasure Agent (td-agent) 4, td-agent v4 was reached EOL in Dec, 2023.
After reached EOL, td-agent v4.5.3 on Windows was released because there was a crash bug during startup on Windows. It was backported fix from fluent-package v5 as it is critical in some case. Even though this was a exceptional maintenance release, but there is no change to the fact that we already stopped maintaining td-agent v4.
We strongly recommend migrating from td-agent v4 to fluent-package v5 (LTS). See Upgrade to fluent-package v5
Hi users!
We had launched fluent-package v5 series last year, recently shipped v5.0.4 in LTS release channel and
v5.1.0 in normal release channel.
In this blog article, we explains the planned next major updates - v6.0.0.
In short, we will ship fluent-package v6 in Aug, 2025.
We keeps two release channels as follows:
Here is the difference of these channels.
fluent-package v7.0.0, and will be shipped in 2027 (T.B.D.).As for fluent-package v6,
Current releases and future plans:
| Release Version | Release Date | End of life |
|---|---|---|
| v5.0.x (LTS) | Aug, 2023 | Dec, 2025 |
| v6.0.0 (LTS) | Aug, 2025 | Dec, 2027 (T.B.D.) |
| v7.0.0 (LTS) | Aug, 2027 (T.B.D.) | T.B.D. |
Happy logging!
Fluentd is an open source data collector to simplify log management.
2024-08-29: Scheduled support lifecycle announcement about Fluent Package v6
2023-08-29: Drop schedule announcement about EOL of Treasure Agent (td-agent) 4
2023-08-29: Scheduled support lifecycle announcement about Fluent Package
2023-07-31: Upgrade to fluent-package v5
2025-05-16: fluent-package v5.0.7 has been released
2025-05-14: Fluentd v1.16.9 has been released
2025-05-01: Fluentd v1.16.8 has been released
2025-03-14: Drop Alpine and switch default to Debian for Fluentd docker image
2025-02-14: fluent-package v5.0.6 has been released
2025-01-29: Fluentd v1.16.7 has been released
2024-12-14: fluent-package v5.2.0 has been released
2024-11-29: Fluentd v1.18.0 has been released
2024-11-08: fluent-package v5.0.5 has been released
2024-08-29: Scheduled support lifecycle announcement about Fluent Package v6
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