OpenTelemetry

Release date 2026/09/15

Feature

• Added a metrics.enable_principal_attribute config option. When enabled, the principal attributes are added to the metrics when an authenticated principal is available.

• Added the log fields that plugins set with kong.log.set_serialize_value to the access log export, so users no longer need custom_attributes_by_lua to deliver them.

Bugfix

• Fixed gen_ai.client.token.usage never reporting token counts for non-text-generation AI categories (image, video, realtime, and audio transcription generation), because it only read the legacy prompt_tokens/prompt_tokens_details analytics log fields instead of falling back to the input_tokens/input_tokens_details fields those categories are logged under.

• Fixed an issue where a custom_attributes_by_lua key that conflicts with an existing log field stopped the log handlers of the plugins that run later.

• Fixed an issue where metrics were rarely (or never) exported on data planes whose configuration is rebuilt more frequently than the metrics push_interval. The periodic metrics push timer is no longer cancelled and recreated on every configuration rebuild, so its push_interval countdown is preserved.

• Fixed an issue where OpenTelemetry metrics only supported integer values by adding support for floating-point values in the OTLP exporter.

• Fixed an issue where the kong.dp.cluster_cert.expiry metric reused the same datapoint timestamp across exports, causing monitoring systems to treat the series as stale.

• Reduced per-request overhead of resource_attributes by skipping template rendering entirely for static (non-templated) fields.

Performance

• Reduced memory usage of the access log queue by deferring OTLP payload conversion to export time.

Release date 2026/09/16

Bugfix

• Fixed an issue where a custom_attributes_by_lua key that conflicts with an existing log field stopped the log handlers of the plugins that run later.

• Fixed an issue where metrics were rarely (or never) exported on data planes whose configuration is rebuilt more frequently than the metrics push_interval. The periodic metrics push timer is no longer cancelled and recreated on every configuration rebuild, so its push_interval countdown is preserved.

Release date 2026/08/24

Bugfix

• Fixed an issue where the kong.dp.cluster_cert.expiry metric reused the same datapoint timestamp across exports, causing monitoring systems to treat the series as stale.

• Reduced per-request overhead of resource_attributes by skipping template rendering entirely for static (non-templated) fields.

Performance

• Reduced memory usage of the access log queue by deferring OTLP payload conversion to export time.

Release date 2026/08/20

Bugfix

• Fixed gen_ai.client.token.usage never reporting token counts for non-text-generation AI categories (image, video, realtime, and audio transcription generation), because it only read the legacy prompt_tokens/prompt_tokens_details analytics log fields instead of falling back to the input_tokens/input_tokens_details fields those categories are logged under.

Release date 2026/07/02

Feature

• Added support for the OTEL_RESOURCE_ATTRIBUTES environment variable. You can now set custom resource attributes for OpenTelemetry instrumentation as secondary resource attributes to the resource_attributes configuration.

Bugfix

• Fixed an issue where request-scoped resource_attributes could leak across concurrent queued traces, logs, and access log exports when the plugin was configured globally.

• Fixed an issue where template resource_attributes in plugin configuration didn’t work as expected for metrics.

• Fixed an issue where the plugin crashed when DNS or balancer failures occurred during upstream retries.

Performance

• Reduced the OTel trace-pipeline CPU overhead.

Release date 2026/09/17

Bugfix

• Fixed an issue where a custom_attributes_by_lua key that conflicts with an existing log field stopped the log handlers of the plugins that run later.

Release date 2026/08/26

Bugfix

• Fixed an issue where metrics were rarely (or never) exported on data planes whose configuration is rebuilt more frequently than the metrics push_interval. The periodic metrics push timer is no longer canceled and recreated on every configuration rebuild, so its push_interval countdown is preserved.

• Fixed an issue where the kong.dp.cluster_cert.expiry metric reused the same datapoint timestamp across exports, causing monitoring systems to treat the series as stale.

• Reduced per-request overhead of resource_attributes by skipping template rendering entirely for static (non-templated) fields.

Performance

• Reduced memory usage of the access log queue by deferring OTLP payload conversion to export time.

Release date 2026/08/19

Bugfix

• Fixed gen_ai.client.token.usage never reporting token counts for non-text-generation AI categories (image, video, realtime, and audio transcription generation), because it only read the legacy prompt_tokens/prompt_tokens_details analytics log fields instead of falling back to the input_tokens/input_tokens_details fields those categories are logged under.

Release date 2026/06/23

Bugfix

• Fixed an issue where request-scoped resource_attributes could leak across concurrent queued traces, logs, and access log exports when the plugin was configured globally.

• Fixed an issue where the plugin crashed when DNS or balancer failures occurred during upstream retries.

Release date 2026/06/04

Bugfix

• Fixed an issue where template ‘resource_attributes’ in configuration of the plugin could not work as expected for metrics.

Release date 2026/04/07

Feature

• Added support for AI/MCP access log

• Added the Konnect Cluster ID and the optional Cluster Member ID to access logs.

• Added support for customizing access logs via Lua code snippets. The previous access_logs_endpoint schema field has been deprecated in favor of a new access_logs.endpoint field, which can be used alongside the access_logs.custom_attributes_by_lua field to specify Lua code snippets for custom attributes.

• Added support for AI/MCP metrics

• Add Konnect Cluster ID and the optional Cluster Member ID attributes to OpenTelemetry metrics in Konnect mode.

• Added support for official MCP metrics

• Support WebSocket related metrics to OpenTelemetry plugin for enhanced observability.

Bugfix

• Fixed an issue where invalid x-b3-flags header values caused 500 responses.

• Fixed an issue where valid response codes from vendor endpoints were incorrectly rejected when exporting traces, logs or metrics.

• Fixed an issue where the http.response.status_code attribute of the http.server.request.count metric was incorrectly set to kong.response.status_code. Now, the attribute name follows the OTel specification.

• Fixed an issue where the kong.upstream.status_code field of access logs was incorrectly populated with string value instead of integer value when there was one or more retries to the upstream.

Release date 2026/08/20

Bugfix

• Fixed an issue where the kong.dp.cluster_cert.expiry metric reused the same datapoint timestamp across exports, causing monitoring systems to treat the series as stale.

Release date 2026/06/30

Bugfix

• Fixed an issue where template ‘resource_attributes’ in configuration of the plugin could not work as expected for metrics.

• Fixed an issue where the plugin crashed when DNS or balancer failures occurred during upstream retries.

Release date 2026/04/08

Bugfix

• Fixed an issue where invalid x-b3-flags header values caused 500 responses.

Release date 2026/02/01

Bugfix

• Fixed an issue where the http.response.status_code attribute of the http.server.request.count metric was incorrectly set to kong.response.status_code. Now, the attribute name follows the OTel specification.

• Fixed an issue where the kong.upstream.status_code field of access logs was incorrectly populated with string value instead of integer value when there was one or more retries to the upstream.

Release date 2025/12/18

Feature

• Added support for exporting OpenTelemetry metrics via OTLP/HTTP protocol to an observability backend (e.g. OpenTelemetry Collector). Please enable this feature by configuring the metrics.endpoint parameter in the OpenTelemetry plugin.

• Added support for exporting access logs via OTLP/HTTP protocol to an observability backend (e.g. OpenTelemetry Collector). Please enable this feature by configuring the access_logs_endpoint parameter in the OpenTelemetry plugin.

Bugfix

• Fixed an issue where the instrumentation started unexpectedly on control planes of hybird mode.

• Fixed an issue where the reference removing did not match the correct property in otel logs.

Release date 2026/02/26

Bugfix

• Fixed an issue where invalid x-b3-flags header values caused 500 responses.

• Fixed an issue where the instrumentation started unexpectedly on control planes of hybird mode.

Release date 2025/10/01

Feature

• Added the peer.service attribute to the balancer span to link multiple services together. This allows for better tracing of requests that span multiple services.

Release date 2026/02/26

Bugfix

• Fixed an issue where invalid x-b3-flags header values caused 500 responses.

• Fixed an issue where the instrumentation started unexpectedly on control planes of hybird mode.

Release date 2025/07/03

Feature

• Added a new configuration field sampling_strategy to the plugin. The field allowed you to specify the sampling strategies for OTLP traces. Set parent_drop_probability_fallback if you want parent-based sampling when the parent span contains a false sampled flag, and fallback to probability-based sampling otherwise. Set parent_probability_fallback if you want parent-based sampling when the parent span contains a valid sampled flag (true or false), and fallback to probability-based sampling otherwise. The default value is parent_drop_probability_fallback and keeps the instrumentation, sampling and exporting behaviour as before.

Release date 2026/02/11

Bugfix

• Fixed an issue where invalid x-b3-flags header values caused 500 responses.

• Fixed an issue where the instrumentation started unexpectedly on control planes of hybird mode.

Release date 2025/03/27

Feature

• This plugin now supports variable resource attributes.

• This plugin now supports instana headers in propagation.

Release date 2024/09/11

Feature

• Added support for OpenTelemetry formatted logs.

Bugfix

• Fixed an issue where migration fails when upgrading from below version 3.3 to 3.7.

• remove redundant deprecation warnings

• Improved accuracy of sampling decisions.

Release date 2024/05/28

Feature

• The propagation module has been reworked. The new options allow better control over the configuration of tracing headers propagation.

Bugfix

• Fixed an OTEL sampling mode Lua panic bug, which happened when the http_response_header_for_traceid option was enabled.

Performance

• Increased queue max batch size to 200.

Release date 2024/10/11

Bugfix

• Fixed an issue where header_type being nil caused a concatenation error.

Release date 2024/04/16

Bugfix

• Improved robustness of parsing for short trace IDs.

Release date 2024/02/26

Bugfix

• fix otel sampling mode lua panic bug when http_response_header_for_traceid option enable

Performance

• increase queue max batch size to 200

Release date 2024/05/20

Bugfix

• fix otel sampling mode lua panic bug when http_response_header_for_traceid option enable

Performance

• increase queue max batch size to 200

Release date 2023/11/08

Feature

• A new value is added to the parameter header_type, which allows Kong to inject datadog headers into the headers of requests forwarding to upstream.

Bugfix

• fix an issue that resulted in invalid parent IDs in the propagated tracing headers

• fix an issue that resulted in traces with invalid parent IDs when balancer instrumentation was enabled

Release date 2026/01/07

Bugfix

• Fixed an issue where the instrumentation started unexpectedly on control planes of hybird mode.

Release date 2024/11/15

Bugfix

• Fixed an issue where header_type being nil caused a concatenation error.

Release date 2024/03/21

Bugfix

• fix otel sampling mode lua panic bug when http_response_header_for_traceid option enable

Performance

• increase queue max batch size to 200

Release date 2023/11/10

Bugfix

• fix an issue that resulted in traces with invalid parent IDs when balancer instrumentation was enabled

Release date 2023/09/28

Feature

• A new value is added to the parameter header_type, which allows Kong to inject datadog headers into the headers of requests forwarding to upstream.

Bugfix

• fix an issue that resulted in invalid parent IDs in the propagated tracing headers

• fix an issue that resulted in invalid parent IDs in the propagated tracing headers

Release date 2023/08/09

Feature

• Introduced support for the AWS X-Ray propagation header. The field header_typenow accepts the aws value to handle this specific propagation header.#11075

• The endpoint parameter is now referenceable, and can be stored as a secret in a vault.#11220

Release date 2023/10/12

Bugfix

• fix an issue that resulted in invalid parent IDs in the propagated tracing headers

Release date 2023/05/19

Feature

• These plugins now convert traceid in HTTP response headers to hex format.#10534

• Spans are now correctly correlated in downstream Datadog traces.10531

• Added the header_type field. Previously, the header_type was hardcoded to preserve. Now it can be set to one of the following values: preserve, ignore, b3, b3-single,w3c, jaeger, or ot.#10620

• Added the new span attribute http.client_ip to capture the client IP when behind a proxy.#10723

• Added the http_response_header_for_traceid configuration parameter. Setting a string value in this field sets a corresponding header in the response.#10379

Bugfix

• Fixed an issue where reconfiguring the plugin didn’t take effect.

• Fixed an issue that caused spans to be propagated incorrectly resulting in the wrong hierarchy being rendered on tracing backends.#10663

Release date 2023/02/28

Feature

• This plugin can now be scoped to individual services, routes, and consumers.#10096

Bugfix

• Fixed an issue in these plugins’ batch queue processing, where metrics would be published multiple times. This caused a memory leak, where memory usage would grow without limit.#10052 #10044

• Fixed non-compliances to specification:

  • For http.uri in spans, the field is now the full HTTP URI. #10036
  • http.status_code is now present on spans for requests that have a status code. #10160
  • http.flavor is now a string value, not a double. #10160

• For http.uri in spans, the field is now the full HTTP URI. #10036

• http.status_code is now present on spans for requests that have a status code. #10160

• http.flavor is now a string value, not a double. #10160

• Fixed an issue with getting the traces of other formats, where the trace ID reported and propagated could be of incorrect length. This caused traces originating from Kong Gateway to incorrectly connect with the target service, causing Kong Gateway and the target service to submit separate traces.#10332

Release date 2023/01/24

Bugfix

• Fixed an issue in these plugins’ batch queue processing, where metrics would be published multiple times. This caused a memory leak, where memory usage would grow without limit.

Release date 2022/12/06

Feature

• Added referenceable attribute to the headers field that could be stored in vaults.#9611

Bugfix

• Fixed an issue that the default propagation header was not configured to w3c correctly.#9457

• Replaced the worker-level table cache withBatchQueue to avoid data race.#9504

• Fixed an issue that the parent_id was not set on the span when propagating w3c traceparent.#9628