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!
Hi users!
We have released v1.16.6 on 2024-08-20. ChangeLog is here.
This release is a maintenance release of v1.16 series. In this release, some bugs were fixed with backporting from v1.17.x.
yaml_parser: $log_level notation in YAML was supportedIn this release, we added a support for $log_level in YAML config file syntax.
In the previous versions, if you used log_level in YAML configuration, it causes a following warning:
[warn]: #0 'log_level' is deprecated parameter name. use '@log_level' instead.
But @log_level is invalid in YAML format. In YAML format, it should be $log_level as same as
similar parameter such as $tag and $type, but not supported before.
Since Fluentd v1.16.6, $log_level has been supported! (In v1.17.x, it was supported since v1.17.1)
--plugin (-p) option not to overwrite default valueIn this release, we have fixed a bug that fluentd command: --plugin (-p) option could not overwrite default value.
This bug was unexpectedly introduced since v1.16.0.
Now it was reverted to the original behavior.
In this release, we fixed a LoadError with console gem v1.25 or later.
Since console gem v1.25 or later, it's internal change causes a LoadError in Fluentd. This error breaks existing plugin such as fluent-plugin-prometheus which provides monitoring REST API.
With supporting console gem v1.25 or later, this issue has solved!
Enjoy logging!
Hi users!
We have released v1.17.1 on 2024-08-19. ChangeLog is here.
This release is a new release of v1.17 series. In this release, we added some new options for some plugins and fixed bugs of Parser.
yaml_parser: $log_level notation in YAML was supportedIn this release, we added a support for $log_level in YAML config file syntax.
In the previous versions, if you used log_level in YAML configuration, it causes a following warning:
[warn]: #0 'log_level' is deprecated parameter name. use '@log_level' instead.
But @log_level is invalid in YAML format. In YAML format, it should be $log_level as same as
similar parameter such as $tag and $type, but not supported before.
Since Fluentd v1.17.1, $log_level has been supported now!
out_http: compress option was supportedIn this release, we added a new option compress for the out_http plugin.
You can compress HTTP request body by specifying compress gzip.
To keep compatibility, the default configuration is set as compress text (no compression).
This feature was contributed by @rockliffelewis. Thanks!
in_sample: the default behavior was changedIn this release, we changed the default behavior of in_sample plugin and added a new option reuse_record for it.
The default behavior has changed to copy sample data to avoid the impact of destructive changes by subsequent plugins.
In the previous versions, when in_sample plugin is used with the subsequent filter parser plugin which uses remove_key_name_field, it raises the following error repeatedly.
#0 dump an error event: error_class=ArgumentError error="message does not exist"
This error occurs when key_name and remove_key_name_field removes key from record with destructive change in filter parser.
It affects generated sample data after twice or later.
(This error is not limited to filter parser plugin. The similar destructive change will be done with the subsequent plugins, this error is reproducible)
The new default behavior (reuse_record false) avoids this problem, but it increases the load when generating large amounts of sample data.
You can use this new parameter to have the same performance as before with reuse_record.
In this release, we fixed a LoadError with console gem v1.25 or later.
Since console gem v1.25 or later, it's internal change causes a LoadError in Fluentd. This error breaks existing plugin such as fluent-plugin-prometheus which provides monitoring REST API.
With supporting console gem v1.25 or later, this issue has solved!
Enjoy logging!
Hi users!
We have released fluent-package v5.1.0. fluent-package is a stable distribution package of Fluentd. (successor of td-agent v4)
This release is a new release of v5.1 series. Bundled ruby version was upgraded to 3.2.5 and fluentd v1.17.0 was shipped!
In this release, focused on updating bundled ones.
In LTS version, conservative updating policy is enabled, so updating gem is very limited to bug fix or security fix. In contrast to LTS version, v5.1.0 bundles more recent components because of standard version.
As we already announced in Scheduled support lifecycle announcement about Fluent Package blog article, in normal release channel, we will ship the latest version (v1.17.0) of Fluentd.
So if you want to try using latest version of Fluentd, v5.1.0 is one for you. If you use fluent-package in enterprise services, keep using fluent-package 5.0.x (LTS).
Please see the download page.
We plan to ship the next LTS version of fluent-package v5.0.5 on Oct, 2024. 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 fluent-package v5.0.4. 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 3.2.4 and a foolproof mechanism was implemented to prevent launching duplicated Fluentd instances, we recommend upgrading to fluent-package v5.0.4!
In this release, a foolproof mechanism was implemented to prevent launching Fluentd wrongly if the service is already running.
As you know, you can check the version of Fluentd with fluentd --version, but there is a case that fluentd -v is executed wrongly to
do it.
When already running Fluentd as a service, fluentd -v launches a duplicated Fluentd instance with the same fluentd configuration.
If you launch duplicated Fluentd instances, it causes the corruption of processing Fluentd buffer.
To prevent such a situation, a foolproof was implemented now.
For example, if Fluentd is running as a service, launching Fluentd causes an error to block it.
Here is the example on Windows:
> fluentd
Error: Can't start duplicate Fluentd instance with the default config.
To start Fluentd, please do one of the following:
(Caution: Please be careful not to start multiple instances with the same config.)
- Stop the Fluentd Windows service 'fluentdwinsvc'.
- Specify the config path explicitly by '-c' ('--config').
Even though if you wrongly launch Fluentd to check version with -v (It should be --version to show version), then it causes the following error.
> fluentd -v
Error: Can't start duplicate Fluentd instance with the default config.
To take the version, please use '--version', not '-v' ('--verbose').
To start Fluentd, please do one of the following:
(Caution: Please be careful not to start multiple instances with the same config.)
- Stop the Fluentd Windows service 'fluentdwinsvc'.
- Specify the config path explicitly by '-c' ('--config')
Note that this foolproof feature is intended to block launching duplicated Fluentd instance, you can explicitly launch Fluentd by specifying a specific option to pass it even though already Fluentd is running as a service.
On Windows:
-c (--config)--dry-run--reg-winsvc--reg-winsvc-fluentdopt--show-plugin-configOn Linux:
-c (--config)--dry-run--show-plugin-configWe plan to ship the next LTS version of fluent-package v5.0.5 on Oct, 2024. 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
Please see the download page.
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
2025-03-14: 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
2024-08-20: Fluentd v1.16.6 has been released
2024-08-19: Fluentd v1.17.1 has been released
2024-08-02: fluent-package v5.1.0 has been released
Want to learn the basics of Fluentd? Check out these pages.
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Fluentd is a hosted project under the Cloud Native Computing Foundation (CNCF). All components are available under the Apache 2 License.