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[ aws . xray ]



Creates a rule to control sampling behavior for instrumented applications. Services retrieve rules with GetSamplingRules , and evaluate each rule in ascending order of priority for each request. If a rule matches, the service records a trace, borrowing it from the reservoir size. After 10 seconds, the service reports back to X-Ray with GetSamplingTargets to get updated versions of each in-use rule. The updated rule contains a trace quota that the service can use instead of borrowing from the reservoir.

See also: AWS API Documentation

See 'aws help' for descriptions of global parameters.


--sampling-rule <value>
[--cli-input-json <value>]
[--generate-cli-skeleton <value>]


--sampling-rule (structure)

The rule definition.

Shorthand Syntax:


JSON Syntax:

  "RuleName": "string",
  "RuleARN": "string",
  "ResourceARN": "string",
  "Priority": integer,
  "FixedRate": double,
  "ReservoirSize": integer,
  "ServiceName": "string",
  "ServiceType": "string",
  "Host": "string",
  "HTTPMethod": "string",
  "URLPath": "string",
  "Version": integer,
  "Attributes": {"string": "string"

--cli-input-json (string) Performs service operation based on the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, the CLI values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See 'aws help' for descriptions of global parameters.


To create a sampling rule

The following create-sampling-rule example creates a rule to control sampling behavior for instrumented applications. The rules are provided by a JSON file. The majority of the sampling rule fields are required to create the rule.

aws xray create-sampling-rule \
    --cli-input-json file://9000-base-scorekeep.json

Contents of 9000-base-scorekeep.json:

    "SamplingRule": {
        "RuleName": "base-scorekeep",
        "ResourceARN": "*",
        "Priority": 9000,
        "FixedRate": 0.1,
        "ReservoirSize": 5,
        "ServiceName": "Scorekeep",
        "ServiceType": "*",
        "Host": "*",
        "HTTPMethod": "*",
        "URLPath": "*",
        "Version": 1


    "SamplingRuleRecord": {
        "SamplingRule": {
            "RuleName": "base-scorekeep",
            "RuleARN": "arn:aws:xray:us-west-2:123456789012:sampling-rule/base-scorekeep",
            "ResourceARN": "*",
            "Priority": 9000,
            "FixedRate": 0.1,
            "ReservoirSize": 5,
            "ServiceName": "Scorekeep",
            "ServiceType": "*",
            "Host": "*",
            "HTTPMethod": "*",
            "URLPath": "*",
            "Version": 1,
            "Attributes": {}
        "CreatedAt": 1530574410.0,
        "ModifiedAt": 1530574410.0

For more information, see Configuring Sampling, Groups, and Encryption Settings with the AWS X-Ray API in the AWS X-Ray Developer Guide.


SamplingRuleRecord -> (structure)

The saved rule definition and metadata.

SamplingRule -> (structure)

The sampling rule.

RuleName -> (string)

The name of the sampling rule. Specify a rule by either name or ARN, but not both.

RuleARN -> (string)

The ARN of the sampling rule. Specify a rule by either name or ARN, but not both.

ResourceARN -> (string)

Matches the ARN of the AWS resource on which the service runs.

Priority -> (integer)

The priority of the sampling rule.

FixedRate -> (double)

The percentage of matching requests to instrument, after the reservoir is exhausted.

ReservoirSize -> (integer)

A fixed number of matching requests to instrument per second, prior to applying the fixed rate. The reservoir is not used directly by services, but applies to all services using the rule collectively.

ServiceName -> (string)

Matches the name that the service uses to identify itself in segments.

ServiceType -> (string)

Matches the origin that the service uses to identify its type in segments.

Host -> (string)

Matches the hostname from a request URL.

HTTPMethod -> (string)

Matches the HTTP method of a request.

URLPath -> (string)

Matches the path from a request URL.

Version -> (integer)

The version of the sampling rule format (1 ).

Attributes -> (map)

Matches attributes derived from the request.

key -> (string)

value -> (string)

CreatedAt -> (timestamp)

When the rule was created.

ModifiedAt -> (timestamp)

When the rule was last modified.