Core configuration optionsedit


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.

The service name must conform to this regular expression: ^[a-zA-Z0-9 _-]+$. In less regexy terms: Your service name must only contain characters from the ASCII alphabet, numbers, dashes, underscores and spaces. Characters in service name which don’t match regular expression will be replaced by _ symbol.

Environment variable name IConfiguration or Web.config key



Default Type

Name of the entry assembly


ServiceNodeName ( [1.3] Added in 1.3. )edit

Optional name used to differentiate between nodes in a service. If not set, data aggregations will be done based on a container ID (where valid) or on the reported hostname (automatically discovered).

This feature requires APM Server versions >= 7.5

Environment variable name IConfiguration or Web.config key



Default Type




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.

Environment variable name IConfiguration or Web.config key



Default Type

Informational version of the entry assembly


Environment ( [1.1] Added in 1.1. )edit

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 Kibana UI for more information.

This feature is fully supported in the APM app in Kibana versions >= 7.2. You must use the query bar to filter for a specific environment in versions prior to 7.2.

Environment variable name IConfiguration or Web.config key



Default Type

See note below


On ASP.NET Core application the agent uses EnvironmentName from IHostingEnvironment as default environment name.


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

When parsing the value for this option, the agent doesn’t consider the current culture. It also expects that a period (.) is used to separate the integer and the fraction of a floating-point number.

This setting can be changed after agent’s start.

Environment variable name IConfiguration or Web.config key



Default Type



TransactionMaxSpans (performance) ( [1.1.1] Added in 1.1.1. )edit

Limits the amount of spans that are recorded per transaction. This is helpful in cases where a transaction creates a very high amount of spans, for example, thousands of SQL queries. Setting an upper limit helps prevent overloading the Agent and APM server in these edge cases.

A value of 0 means that spans will never be collected. Setting -1 means that spans will never be dropped. The Agent will revert to the default value if the value is set below -1.

This setting can be changed after agent’s start.

Environment variable name IConfiguration key



Default Type



CentralConfig ( [1.1] Added in 1.1. )edit

If set to true, the agent makes periodic requests to the APM Server to fetch the latest APM Agent configuration.

Environment variable name IConfiguration key



Default Type



SanitizeFieldNames ( [1.2] Added in 1.2. )edit

Sometimes it is necessary to sanitize, i.e., remove, sensitive data sent to Elastic APM. This config accepts a list of wildcard patterns of field names which should be sanitized. These apply for example to HTTP headers and application/x-www-form-urlencoded data.

This setting only applies to values that are captured automatically by the agent. If you capture the request body manually with the public API, this configuration doesn’t apply, and the agent won’t sanitize the body.

The wildcard, *, matches zero or more characters, and matching is case insensitive by default. Prepending an element with (?-i) makes the matching case sensitive. Examples: /foo/*/bar/*/baz*, *foo*.

You should review the data captured by Elastic APM carefully to make sure it does not contain sensitive information. If you do find sensitive data in your Elasticsearch index, you should add an additional entry to this list. Make sure to include the default entries as well, as setting a value here will overwrite the defaults.

Data in the query string is considered non-sensitive, as sensitive information should not be sent in the query string. See for more information.

Environment variable name IConfiguration key



Default Type

password, passwd, pwd, secret, *key, *token*, *session*, *credit*, *card*, authorization, set-cookie


GlobalLabels ( [1.2] Added in 1.2. )edit

Labels added to all events, with the format key=value[,key=value[,...]]. Any labels set by the application via the agent’s public API will override global labels with the same keys.

Environment variable name IConfiguration key



Default Type

<empty map>

Map of string to string

This option requires APM Server 7.2 or later. It will have no effect on older versions.