Table Of Contents


User Guide

First time using the AWS CLI? See the User Guide for help getting started.

Note: You are viewing the documentation for an older major version of the AWS CLI (version 1).

AWS CLI version 2, the latest major version of AWS CLI, is now stable and recommended for general use. To view this page for the AWS CLI version 2, click here. For more information see the AWS CLI version 2 installation instructions and migration guide.

[ aws . xray ]



Modifies a sampling rule's configuration.

See also: AWS API Documentation

See 'aws help' for descriptions of global parameters.


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


--sampling-rule-update (structure)

The rule and fields to change.

Shorthand Syntax:


JSON Syntax:

  "RuleName": "string",
  "RuleARN": "string",
  "ResourceARN": "string",
  "Priority": integer,
  "FixedRate": double,
  "ReservoirSize": integer,
  "Host": "string",
  "ServiceName": "string",
  "ServiceType": "string",
  "HTTPMethod": "string",
  "URLPath": "string",
  "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 update a sampling rule

The following update-sampling-rule example modifies a sampling rule's configuration. The rules are consumed from a JSON file. Only the fields being updated are required.

aws xray update-sampling-rule \
   --cli-input-json file://1000-default.json

Contents of 1000-default.json:

    "SamplingRuleUpdate": {
        "RuleName": "Default",
        "FixedRate": 0.01,
        "ReservoirSize": 0


    "SamplingRuleRecords": [
            "SamplingRule": {
                "RuleName": "Default",
                "RuleARN": "arn:aws:xray:us-west-2:123456789012:sampling-rule/Default",
                "ResourceARN": "*",
                "Priority": 10000,
                "FixedRate": 0.01,
                "ReservoirSize": 0,
                "ServiceName": "*",
                "ServiceType": "*",
                "Host": "*",
                "HTTPMethod": "*",
                "URLPath": "*",
                "Version": 1,
                "Attributes": {}
            "CreatedAt": 0.0,
            "ModifiedAt": 1529959993.0

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 updated 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.