Adapt the Elastic APM Go agent to your needs with one of the following methods—​listed in descending order of precedence:

Configuration defined via Kibana will take precedence over the same configuration defined in code, which takes precedence over environment variables. If configuration is defined via Kibana, and then that is later removed, the agent will revert to configuration defined locally via either the Tracer Config API or environment variables.

To simplify development and testing, the agent defaults to sending data to the Elastic APM Server at http://localhost:8200. To send data to an alternative location, you must configure ELASTIC_APM_SERVER_URL. Depending on the configuration of your server, you may also need to set ELASTIC_APM_API_KEY, ELASTIC_APM_SECRET_TOKEN, and ELASTIC_APM_VERIFY_SERVER_CERT. All other variables have usable defaults.

Dynamic configurationedit

Configuration options marked with the badge can be changed at runtime when set from a supported source.

The Go Agent supports Central configuration, which allows you to fine-tune certain configurations via the APM app. This feature is enabled in the Agent by default, with ELASTIC_APM_CENTRAL_CONFIG.

Configuration formatsedit

Some options require a unit, either duration or size. These need to be provided in a specific format.

Duration formatedit

The duration format is used for options like timeouts. The unit is provided as a suffix directly after the number, without any whitespace.

Example: 5ms

Supported units:

Size formatedit

The size format is used for options such as maximum buffer sizes. The unit is provided as a suffix directly after the number, without any whitespace.

Example: 10KB

Supported units:

ELASTIC_APM_SERVER_URLedit

The URL for your Elastic APM Server. The Server supports both HTTP and HTTPS. If you use HTTPS, then you may need to configure your client machines so that the server certificate can be verified. You can disable certificate verification with ELASTIC_APM_VERIFY_SERVER_CERT.

ELASTIC_APM_SERVER_TIMEOUTedit

The timeout for requests made to your Elastic APM server. When set to zero or a negative value, timeouts will be disabled.

ELASTIC_APM_SECRET_TOKENedit

This string is used to ensure that only your agents can send data to your APM server. Both the agents and the APM server have to be configured with the same secret token.

ELASTIC_APM_API_KEYedit

This base64-encoded string is used to ensure that only your agents can send data to your APM server. The API key must be created using the APM Server command line tool.

ELASTIC_APM_SERVICE_NAMEedit

The name of your service or application. This is used to keep all the errors and transactions of your service together and is the primary filter in the Elastic APM user interface.

If you do not specify ELASTIC_APM_SERVICE_NAME, the Go agent will use the executable name. e.g. if your executable is called "my-app.exe", then your service will be identified as "my-app".

ELASTIC_APM_SERVICE_VERSIONedit

A version string for the currently deployed version of the service. If you don’t version your deployments, the recommended value for this field is the commit identifier of the deployed revision, e.g. the output of git rev-parse HEAD.

ELASTIC_APM_SERVICE_NODE_NAMEedit

Optional name used to differentiate between nodes in a service. Must be unique, otherwise data from multiple nodes will be aggregated together.

If you do not specify ELASTIC_APM_SERVICE_NODE_NAME, service nodes will be identified using the container ID if available, otherwise the host name.

ELASTIC_APM_ENVIRONMENTedit

The name of the environment this service is deployed in, e.g. "production" or "staging".

Environments allow you to easily filter data on a global level in the APM app. It’s important to be consistent when naming environments across agents. See environment selector in the APM app for more information.

ELASTIC_APM_ACTIVEedit

Enable or disable the agent. If set to false, then the Go agent does not send any data to the Elastic APM server, and instrumentation overhead is minimized.

ELASTIC_APM_RECORDINGedit

Enable or disable recording of events. If set to false, then the Go agent does not send any events to the Elastic APM server, and instrumentation overhead is minimized, but the agent will continue to poll the server for configuration changes.

ELASTIC_APM_GLOBAL_LABELSedit

Labels are added to all events. The format for labels is: key=value[,key=value[,...]]. Any labels set by application via the API will override global labels with the same keys.

This option requires APM Server 7.2 or greater, and will have no effect when using older server versions.

ELASTIC_APM_TRANSACTION_IGNORE_URLSedit

A list of patterns to match HTTP requests to ignore. An incoming HTTP request whose request line matches any of the patterns will not be reported as a transaction.

This option supports the wildcard *, which matches zero or more characters. Examples: /foo/*/bar/*/baz*, *foo*. Matching is case insensitive by default. Prefixing a pattern with (?-i) makes the matching case sensitive.

ELASTIC_APM_SANITIZE_FIELD_NAMESedit

A list of patterns to match the names of HTTP headers, cookies, and POST form fields to redact.

This option supports the wildcard *, which matches zero or more characters. Examples: /foo/*/bar/*/baz*, *foo*. Matching is case insensitive by default. Prefixing a pattern with (?-i) makes the matching case sensitive.

ELASTIC_APM_CAPTURE_HEADERSedit

For transactions that are HTTP requests, the Go agent can optionally capture request and response headers.

Possible values: true, false.

Captured headers are subject to sanitization, per ELASTIC_APM_SANITIZE_FIELD_NAMES.

ELASTIC_APM_CAPTURE_BODYedit

For transactions that are HTTP requests, the Go agent can optionally capture the request body.

Possible values: errors, transactions, all, off.

ELASTIC_APM_HOSTNAMEedit

The host name to use when sending error and transaction data to the APM server.

ELASTIC_APM_API_REQUEST_TIMEedit

The amount of time to wait before ending a request to the Elastic APM server. When you report transactions, spans and errors, the agent will initiate a request and send them to the server when there is enough data to send; the request will remain open until this time has been exceeded, or until the maximum request size has been reached.

ELASTIC_APM_API_REQUEST_SIZEedit

The maximum size of request bodies to send to the Elastic APM server. The agent will maintain an in-memory buffer of compressed data for streaming to the APM server.

ELASTIC_APM_API_BUFFER_SIZEedit

The maximum number of bytes of uncompressed, encoded events to store in memory while the agent is busy. When the agent is able to, it will transfer buffered data to the request buffer, and start streaming it to the server. If the buffer fills up, new events will start replacing older ones.

ELASTIC_APM_TRANSACTION_MAX_SPANSedit

Limits the amount of spans that are recorded per transaction.

This is helpful in cases where a transaction creates a large number of spans (e.g. thousands of SQL queries). Setting an upper limit will prevent overloading the agent and the APM server with too much work for such edge cases.

ELASTIC_APM_EXIT_SPAN_MIN_DURATIONedit

Sets the minimum duration for an exit span to be reported. Spans shorter or equal to this threshold will be dropped by the agent and reported as statistics in the span’s transaction, as long as the transaction didn’t end before the span was reported.

When span compression is enabled (ELASTIC_APM_SPAN_COMPRESSION_ENABLED), the sum of the compressed span composite is considered.

The minimum duration allowed for this setting is 1 microsecond (us).

ELASTIC_APM_SPAN_FRAMES_MIN_DURATIONedit

The APM agent will collect a stack trace for every recorded span whose duration exceeds this configured value. While this is very helpful to find the exact place in your code that causes the span, collecting this stack trace does have some processing and storage overhead.

ELASTIC_APM_SPAN_STACK_TRACE_MIN_DURATIONedit

The APM agent will collect a stack trace for every recorded span whose duration exceeds this configured value. While this is very helpful to find the exact place in your code that causes the span, collecting this stack trace does have some processing and storage overhead.

ELASTIC_APM_STACK_TRACE_LIMITedit

Limits the number of frames captured for each stack trace.

Setting the limit to 0 will disable stack trace collection, while any positive integer value will be used as the maximum number of frames to collect. Setting a negative value, such as -1, means that all frames will be collected.

ELASTIC_APM_TRANSACTION_SAMPLE_RATEedit

By default, the agent will sample every transaction (e.g. request to your service). To reduce overhead and storage requirements, set the sample rate to a value between 0.0 and 1.0. We still record overall time and the result for unsampled transactions, but no context information, tags, or spans.

ELASTIC_APM_METRICS_INTERVALedit

The interval at which APM agent gathers and reports metrics. Set to 0s to disable.

ELASTIC_APM_DISABLE_METRICSedit

Disables the collection of certain metrics. If the name of a metric matches any of the wildcard expressions, it will not be collected.

This option supports the wildcard *, which matches zero or more characters. Examples: /foo/*/bar/*/baz*, *foo*. Matching is case insensitive by default. Prefixing a pattern with (?-i) makes the matching case sensitive.

ELASTIC_APM_BREAKDOWN_METRICSedit

Capture breakdown metrics. Set to false to disable.

ELASTIC_APM_SERVER_CERTedit

If you have configured your APM Server with a self signed TLS certificate, or you want to pin the server certificate, specify the path to the PEM-encoded certificate via the ELASTIC_APM_SERVER_CERT configuration.

ELASTIC_APM_SERVER_CA_CERT_FILEedit

The path to a PEM-encoded TLS Certificate Authority certificate that will be used for verifying the server’s TLS certificate chain.

ELASTIC_APM_VERIFY_SERVER_CERTedit

By default, the agent verifies the server’s certificate if you use an HTTPS connection to the APM server. Verification can be disabled by changing this setting to false. This setting is ignored when ELASTIC_APM_SERVER_CERT is set.

ELASTIC_APM_LOG_FILEedit

ELASTIC_APM_LOG_FILE specifies the output file for the agent’s default, internal logger. The file will be created, or truncated if it exists, when the process starts. By default, logging is disabled. You must specify ELASTIC_APM_LOG_FILE to enable it. This environment variable will be ignored if a logger is configured programatically.

There are two special file names that the agent recognizes: stdout and stderr. These will configure the logger to write to standard output and standard error respectively.

ELASTIC_APM_LOG_LEVELedit

ELASTIC_APM_LOG_LEVEL specifies the log level for the agent’s default, internal logger. The only two levels used by the logger are "error" and "debug". By default, logging is disabled. You must specify ELASTIC_APM_LOG_FILE to enable it.

This environment variable will be ignored if a logger is configured programatically.

ELASTIC_APM_CENTRAL_CONFIGedit

Activate APM Agent central configuration via Kibana. By default the agent will poll the server for agent configuration changes. This can be disabled by changing the setting to false. See APM Agent central configuration for more information.

ELASTIC_APM_USE_ELASTIC_TRACEPARENT_HEADERedit

To enable distributed tracing, the agent adds trace context headers to outgoing HTTP requests made with module/apmhttp. These headers (traceparent and tracestate) are defined in the W3C Trace Context specification.

When this setting is true, the agent will also add the header elastic-apm-traceparent for backwards compatibility with older versions of Elastic APM agents.

ELASTIC_APM_CLOUD_PROVIDERedit

This config value allows you to specify which cloud provider should be assumed for metadata collection. By default, the agent will use trial and error to automatically collect the cloud metadata.

Valid options are "none", "auto", "aws", "gcp", and "azure" If this config value is set to "none", then no cloud metadata will be collected.

ELASTIC_APM_SPAN_COMPRESSION_ENABLEDedit

When enabled, the agent will attempt to compress short exit spans that share the same parent into a composite span. The exact duration for what is considered short, depends on the compression strategy used (same_kind or exact_match).

In order for a span to be compressible, these conditions need to be met:

Compressing short exit spans should provide some storage savings for services that create a lot of consecutive short exit spans to for example databases or cache services which are generally uninteresting when viewing a trace.

ELASTIC_APM_SPAN_COMPRESSION_EXACT_MATCH_MAX_DURATIONedit

The maximum duration to consider for compressing sibling exit spans that are an exact match for compression.

ELASTIC_APM_SPAN_COMPRESSION_SAME_KIND_MAX_DURATIONedit

The maximum duration to consider for compressing sibling exit spans that are of the same kind for compression.

ELASTIC_APM_TRACE_CONTINUATION_STRATEGYedit

This option allows some control over how the APM agent handles W3C trace-context headers on incoming requests. By default, the traceparent and tracestate headers are used per W3C spec for distributed tracing. However, in certain cases it can be helpful to not use the incoming traceparent header. Some example use cases:

Valid options are continue, restart, and restart_external:

Starting with Elastic Observability 8.2, span links are visible in trace views.