This page describes configuration options that behave consistently across all languages. To view these common configuration options, see Common configuration options.

For configuration options specific to your programming language, choose your language from the options below:

To instrument an application written in a language that does not yet have official library support, see the list of community tracing libraries.

Common configuration options

The following configuration options behave consistently across the latest versions of all Datadog SDKs, unless otherwise noted:

Agent

DD_TRACE_AGENT_URL

Default: http://localhost:8126
Supported Input: A string representing an HTTP or UDS url
Description: The URL for connecting the tracer to the Datadog agent. Valid URL schemas include http:// and unix:// (UNIX Domain Sockets). This value takes precedence over DD_AGENT_HOST and DD_TRACE_AGENT_PORT if set.

DD_DOGSTATSD_PORT

Default: 8125
Supported Input: Integer between 0 and 65535
Caveats: Not supported in C++, Ruby, .NET
Description: Specifies the port number for the DogStatsD server to which runtime metrics are sent.

DD_DOGSTATSD_HOST

Default: localhost
Supported Input: String representing a hostname or IP address
Caveats: Not supported in C++, Ruby, .NET
Description: Specifies the hostname or IP address of the DogStatsD server to which runtime metrics are sent.

Unified Service Tagging

DD_VERSION

Default: null
Supported Input: A string representing an application version
Caveats: Node.js defaults to the version number from package.json
Description: Adds a version tag to all spans, except for Inferred services

DD_SERVICE

Default: null, the SDK tries to automatically determine a service name
Supported Input: A string representing an application service name
Description: Sets the default service name used for most spans. SDKs may set a different service name for inferred services. Integration spans may use their own default names, which can differ from the value specified in DD_SERVICE

DD_ENV

Default: null
Supported Input: A string representing an application environment name (for example, prod, dev)
Description: Adds an environment tag to all spans generated by the tracer instance.

DD_TAGS

Default: null
Supported Input: A string representing key value pairs that are delimited by a colon and separated by a comma and/or a space (for example, <key1>:<value1>, <key2>:<value2>>)
Description: Tags to apply to produced data. Must be a list of <key>:<value> separated by commas and/or spaces.

Diagnostics

DD_TRACE_LOG_DIRECTORY

Default: Varies by SDK, environment, and runtime. Please read more in the specific configuration page above for your chosen language
Supported Input: A valid full or relative directory path that exists on the system
Caveats: Not supported in Java, Node.js, Ruby, Python
Description: Specifies the directory where tracer log files should be routed. If the directory does not exist, the SDK falls back to its default diagnostic logging method.

Metrics

DD_RUNTIME_METRICS_ENABLED

Default: false
Supported Input: Boolean (true/false)
Caveats: Not supported in C++ or PHP
Description: Enables or disables the collection of runtime metrics (such as garbage collection stats, memory usage, and thread counts) for the application.

Traces

DD_TRACE_ENABLED

Default: true
Supported Input: Boolean
Description: Enables or disables sending traces from the application.

DD_LOGS_INJECTION

Default: false
Supported Input: Boolean (true/false)
Caveats: Not supported in C++ or Go. The default value in Ruby is true.
Description: Enables or disables the automatic injection of trace context (trace ID, span ID) into application logs. This allows for correlation between traces and logs.

DD_TRACE_SAMPLING_RULES

Default: null
Supported Input: A JSON string representing an array of sampling rules. Each rule must contain a sample_rate (float between 0 and 1) and can optionally include a service (string) and name (string) pattern to match. Example: [{"sample_rate": 0.1, "service": "my-service", "name": "http.request"}]
Description: Configures custom sampling rules for traces. Rules are evaluated in order, and the first matching rule determines the sampling rate. If no rules match, the default sampling rate is used. For more information about how these configurations affect trace ingestion, see Ingestion Mechanisms.

DD_TRACE_RATE_LIMIT

Default: 100
Supported Input: A positive integer
Caveats: 200 is the default value of DD_TRACE_RATE_LIMIT in C++
Description: Sets the maximum number of traces to sample per second; applies only when either DD_TRACE_SAMPLING_RULES or DD_TRACE_SAMPLE_RATE is set.

DD_TRACE_HEADER_TAGS

Default: null
Supported Input: A comma-separated string representing a list of case-insensitive HTTP headers, with an optional mapping to a custom tag name. Example: User-Agent:my-user-agent,Content-Type.
Description: Automatically apply specified HTTP headers as span tags. If a custom tag name is not specified, the tag key defaults to http.request.headers.<normalized-header-name> for request headers and http.response.headers.<normalized-header-name> for response headers.

DD_TRACE_OBFUSCATION_QUERY_STRING_REGEXP

Default:

(?i)(?:(?:"|%22)?)(?:(?:old[-_]?|new[-_]?)?p(?:ass)?w(?:or)?d(?:1|2)?|pass(?:[-_]?phrase)?|secret|(?:api[-_]?|private[-_]?|public[-_]?|access[-_]?|secret[-_]?|app(?:lication)?[-_]?)key(?:[-_]?id)?|token|consumer[-_]?(?:id|key|secret)|sign(?:ed|ature)?|auth(?:entication|orization)?)(?:(?:\s|%20)*(?:=|%3D)[^&]+|(?:"|%22)(?:\s|%20)*(?::|%3A)(?:\s|%20)*(?:"|%22)(?:%2[^2]|%[^2]|[^"%])+(?:"|%22))|(?:bearer(?:\s|%20)+[a-z0-9._\-]+|token(?::|%3A)[a-z0-9]{13}|gh[opsu]_[0-9a-zA-Z]{36}|ey[I-L](?:[\w=-]|%3D)+\.ey[I-L](?:[\w=-]|%3D)+(?:\.(?:[\w.+/=-]|%3D|%2F|%2B)+)?|-{5}BEGIN(?:[a-z\s]|%20)+PRIVATE(?:\s|%20)KEY-{5}[^\-]+-{5}END(?:[a-z\s]|%20)+PRIVATE(?:\s|%20)KEY(?:-{5})?(?:\n|%0A)?|(?:ssh-(?:rsa|dss)|ecdsa-[a-z0-9]+-[a-z0-9]+)(?:\s|%20|%09)+(?:[a-z0-9/.+]|%2F|%5C|%2B){100,}(?:=|%3D)*(?:(?:\s|%20|%09)+[a-z0-9._-]+)?)

Supported Input: A regex string

Description: Applies a regex to redact sensitive data from query strings on incoming HTTP requests. The default regex matches various sensitive data patterns, including passwords, tokens, API keys, private keys, and authorization terms. Matches are replaced with <redacted>. If an empty string is passed, no obfuscation occurs. The resulting value is reported in the http.url tag.

DD_TRACE_128_BIT_TRACEID_GENERATION_ENABLED

Default: true
Supported Input: Boolean (true/false)
Description: Controls whether new traces use 128-bit W3C trace IDs (32-character hexadecimal strings) or 64-bit Datadog trace IDs (16-character hexadecimal strings). The default is true to support W3C trace context propagation.

DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED

Default: true
Supported Input: Boolean (true/false)
Caveats: Not supported in C++
Description: Controls whether 128-bit trace IDs are logged in their full 32-character format or truncated to 16 characters. Set to false for compatibility with systems that expect the shorter format.

DD_TRACE_CLIENT_IP_ENABLED

Default: true
Supported Input: Boolean (true/false)
Caveats: Not supported in C++
Description: Enables or disables the automatic collection of client IP addresses from HTTP request headers. When enabled, the IP address is stored in the http.client_ip span tag.

DD_TRACE_EXPERIMENTAL_FEATURES_ENABLED

Default: null
Supported Input: A comma-separated list of configuration options that support experimental features.
Supported Values: all, DD_TAGS (Java, .NET), DD_LOGS_INJECTION (Java)
Caveats: Only supported in Java and .NET
Description: Enables experimental features for specific configuration options. When enabled, these features may provide additional functionality but are not yet considered stable and may change or be removed in future releases. Each feature must be explicitly listed to be enabled.

Integrations

DD_TRACE_<INTEGRATION>_ENABLED

Default: true
Supported Input: Boolean
Caveats: Not supported in Go; Some Java integrations are disabled by default.
Description: Enables or disables instrumentation for the specified <INTEGRATION>. The integration name must be in uppercase (for example, DD_TRACE_KAFKA_ENABLED=true)

DD_TRACE_HTTP_CLIENT_ERROR_STATUSES

Default: 400-499
Supported Input: A comma-separated string of the form from-to, where from and to are integers. Singular values are also accepted (for example, 400-403,405,410-499).
Caveats: Not supported in Node.js
Description: Defines the inclusive range of status codes to be considered as errors on automatically collected HTTP client spans. Only the values within the specified range are considered errors.

DD_TRACE_HTTP_SERVER_ERROR_STATUSES

Default: 500-599
Supported Input: A comma-separated string of the form from-to, where from and to are integers. Singular values are also accepted (for example, 400-403,405,410-499).
Caveats: Not supported in Node.js
Description: Defines the inclusive range of status codes to be considered errors on http.server span kinds. Only the values within the specified range are considered errors.

DD_TRACE_HTTP_CLIENT_TAG_QUERY_STRING

Default: true
Supported Input: Boolean
Caveats: Not supported in Node.js; Disabled by default in Go
Description: Enables or disables the inclusion of the query string in the http.url span tag value for automatically collected HTTP spans.

DD_TRACE_CLIENT_IP_HEADER

Default: null
Supported Input: Any non-empty string
Description: Configures a custom header name from which to source the http.client_ip tag value. If this variable is set, all other IP-related headers are ignored (for example, setting DD_TRACE_CLIENT_IP_HEADER=custom-ip-header and including the header custom-ip-header: 5.6.7.9 in a request results in a span tagged with "http.client_ip": "5.6.7.9"). If an empty string or null value is passed, IP headers are queried in this order:

• x-forwarded-for
• x-real-ip
• true-client-ip
• x-client-ip
• x-forwarded
• forwarded-for
• x-cluster-client-ip
• fastly-client-ip
• cf-connecting-ip
• cf-connecting-ipv6