agent-config.md

Agent Configuration

NOTE: subject to change!

Note: The environment variables/system properties in this document are very likely to change over time. Please check back here when trying out a new version!

Please report any bugs or unexpected behavior you find.

Contents

• SDK Autoconfiguration
• Peer service name
• DB statement sanitization
• Suppressing specific auto-instrumentation

SDK Autoconfiguration

The SDK's autoconfiguration module is used for basic configuration of the agent. Read the docs to find settings such as configuring export or sampling.

Here are some quick links into those docs for the configuration options for specific portions of the SDK & agent:

• Exporters
  • OTLP exporter (both span and metric exporters)
  • Jaeger exporter
  • Zipkin exporter
  • Prometheus exporter
  • Logging exporter
• Trace context propagation
• OpenTelemetry Resource and service name
• Batch span processor
• Sampler
• Span limits
• Using SPI to further configure the SDK

Peer service name

The peer service name is the name of a remote service being connected to. It corresponds to service.name in the Resource for the local service.

System property	Environment variable	Description
otel.instrumentation.common.peer-service-mapping	OTEL_INSTRUMENTATION_COMMON_PEER_SERVICE_MAPPING	Used to specify a mapping from hostnames or IP addresses to peer services, as a comma-separated list of host=name pairs. The peer service is added as an attribute to a span whose host or IP match the mapping. For example, if set to 1.2.3.4=cats-service,dogs-abcdef123.serverlessapis.com=dogs-api, requests to 1.2.3.4 will have a peer.service attribute of cats-service and requests to dogs-abcdef123.serverlessapis.com will have an attribute of dogs-api.

DB statement sanitization

The agent sanitizes all database queries/statements before setting the db.statement semantic attribute: all values (strings, numbers) in the query string are replaced with a question mark ?.

Examples:

• SQL query SELECT a from b where password="secret" will appear as SELECT a from b where password=? in the exported span;
• Redis command HSET map password "secret" will appear as HSET map password ? in the exported span.

This behavior is turned on by default for all database instrumentations. The following property may be used to disable it:

System property	Environment variable	Description
otel.instrumentation.common.db-statement-sanitizer.enabled	OTEL_INSTRUMENTATION_COMMON_DB_STATEMENT_SANITIZER_ENABLED	Enables the DB statement sanitization. The default value is true.

Suppressing specific auto-instrumentation

See suppressing specific auto-instrumentation