Amazon Route 53 Auto Naming

2018/03/13 - Amazon Route 53 Auto Naming - 1 new 2 updated api methods

Changes  This release adds support for custom health checks, which let you check the health of resources that aren't accessible over the internet. For example, you can use a custom health check when the instance is in an Amazon VPC.

UpdateInstanceCustomHealthStatus (new) Link ¶

See also: AWS API Documentation

Request Syntax

client.update_instance_custom_health_status(
    ServiceId='string',
    InstanceId='string',
    Status='HEALTHY'|'UNHEALTHY'
)
type ServiceId

string

param ServiceId

[REQUIRED]

type InstanceId

string

param InstanceId

[REQUIRED]

type Status

string

param Status

[REQUIRED]

returns

None

CreateService (updated) Link ¶
Changes (request, response)
Request 
{'HealthCheckCustomConfig': {'FailureThreshold': 'integer'}}
Response 
{'Service': {'HealthCheckCustomConfig': {'FailureThreshold': 'integer'}}}

Creates a service, which defines the configuration for the following entities:

  • Up to three records (A, AAAA, and SRV) or one CNAME record

  • Optionally, a health check

After you create the service, you can submit a RegisterInstance request, and Amazon Route 53 uses the values in the configuration to create the specified entities.

For the current limit on the number of instances that you can register using the same namespace and using the same service, see Limits on Auto Naming in the Route 53 Developer Guide .

See also: AWS API Documentation

Request Syntax

client.create_service(
    Name='string',
    CreatorRequestId='string',
    Description='string',
    DnsConfig={
        'NamespaceId': 'string',
        'RoutingPolicy': 'MULTIVALUE'|'WEIGHTED',
        'DnsRecords': [
            {
                'Type': 'SRV'|'A'|'AAAA'|'CNAME',
                'TTL': 123
            },
        ]
    },
    HealthCheckConfig={
        'Type': 'HTTP'|'HTTPS'|'TCP',
        'ResourcePath': 'string',
        'FailureThreshold': 123
    },
    HealthCheckCustomConfig={
        'FailureThreshold': 123
    }
)
type Name

string

param Name

[REQUIRED]

The name that you want to assign to the service.

type CreatorRequestId

string

param CreatorRequestId

A unique string that identifies the request and that allows failed CreateService requests to be retried without the risk of executing the operation twice. CreatorRequestId can be any unique string, for example, a date/time stamp.

This field is autopopulated if not provided.

type Description

string

param Description

A description for the service.

type DnsConfig

dict

param DnsConfig

[REQUIRED]

A complex type that contains information about the records that you want Route 53 to create when you register an instance.

  • NamespaceId (string) -- [REQUIRED]

    The ID of the namespace to use for DNS configuration.

  • RoutingPolicy (string) --

    The routing policy that you want to apply to all records that Route 53 creates when you register an instance and specify this service.

    Note

    If you want to use this service to register instances that create alias records, specify WEIGHTED for the routing policy.

    You can specify the following values:

    MULTIVALUE

    If you define a health check for the service and the health check is healthy, Route 53 returns the applicable value for up to eight instances.

    For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with IP addresses for up to eight healthy instances. If fewer than eight instances are healthy, Route 53 responds to every DNS query with the IP addresses for all of the healthy instances.

    If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the values for up to eight instances.

    For more information about the multivalue routing policy, see Multivalue Answer Routing in the Route 53 Developer Guide .

    WEIGHTED

    Route 53 returns the applicable value from one randomly selected instance from among the instances that you registered using the same service. Currently, all records have the same weight, so you can't route more or less traffic to any instances.

    For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with the IP address for one randomly selected instance from among the healthy instances. If no instances are healthy, Route 53 responds to DNS queries as if all of the instances were healthy.

    If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the applicable value for one randomly selected instance.

    For more information about the weighted routing policy, see Weighted Routing in the Route 53 Developer Guide .

  • DnsRecords (list) -- [REQUIRED]

    An array that contains one DnsRecord object for each record that you want Route 53 to create when you register an instance.

    • (dict) --

      A complex type that contains information about the records that you want Route 53 to create when you register an instance.

      • Type (string) -- [REQUIRED]

        The type of the resource, which indicates the type of value that Route 53 returns in response to DNS queries.

        Note the following:

        • A, AAAA, and SRV records: You can specify settings for a maximum of one A, one AAAA, and one SRV record. You can specify them in any combination.

        • CNAME records: If you specify CNAME for Type , you can't define any other records. This is a limitation of DNS—you can't create a CNAME record and any other type of record that has the same name as a CNAME record.

        • Alias records: If you want Route 53 to create an alias record when you register an instance, specify A or AAAA for Type .

        • All records: You specify settings other than TTL and Type when you register an instance.

        The following values are supported:

        A

        Route 53 returns the IP address of the resource in IPv4 format, such as 192.0.2.44.

        AAAA

        Route 53 returns the IP address of the resource in IPv6 format, such as 2001:0db8:85a3:0000:0000:abcd:0001:2345.

        CNAME

        Route 53 returns the domain name of the resource, such as www.example.com. Note the following:

        • You specify the domain name that you want to route traffic to when you register an instance. For more information, see RegisterInstanceRequest$Attributes .

        • You must specify WEIGHTED for the value of RoutingPolicy .

        • You can't specify both CNAME for Type and settings for HealthCheckConfig . If you do, the request will fail with an InvalidInput error.

        SRV

        Route 53 returns the value for an SRV record. The value for an SRV record uses the following values:

        priority weight port service-hostname

        Note the following about the values:

        • The values of priority and weight are both set to 1 and can't be changed.

        • The value of port comes from the value that you specify for the AWS_INSTANCE_PORT attribute when you submit a RegisterInstance request.

        • The value of service-hostname is a concatenation of the following values:

          • The value that you specify for InstanceId when you register an instance.

          • The name of the service.

          • The name of the namespace.

        For example, if the value of InstanceId is test , the name of the service is backend , and the name of the namespace is example.com , the value of service-hostname is:

        test.backend.example.com

        If you specify settings for an SRV record and if you specify values for AWS_INSTANCE_IPV4 , AWS_INSTANCE_IPV6 , or both in the RegisterInstance request, Route 53 automatically creates A and/or AAAA records that have the same name as the value of service-hostname in the SRV record. You can ignore these records.

      • TTL (integer) -- [REQUIRED]

        The amount of time, in seconds, that you want DNS resolvers to cache the settings for this record.

        Note

        Alias records don't include a TTL because Route 53 uses the TTL for the AWS resource that an alias record routes traffic to. If you include the AWS_ALIAS_DNS_NAME attribute when you submit a RegisterInstance request, the TTL value is ignored. Always specify a TTL for the service; you can use a service to register instances that create either alias or non-alias records.

type HealthCheckConfig

dict

param HealthCheckConfig

Public DNS namespaces only. A complex type that contains settings for an optional health check. If you specify settings for a health check, Route 53 associates the health check with all the records that you specify in DnsConfig .

For information about the charges for health checks, see Route 53 Pricing .

  • Type (string) --

    The type of health check that you want to create, which indicates how Route 53 determines whether an endpoint is healthy.

    Warning

    You can't change the value of Type after you create a health check.

    You can create the following types of health checks:

    • HTTP : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTP request and waits for an HTTP status code of 200 or greater and less than 400.

    • HTTPS : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTPS request and waits for an HTTP status code of 200 or greater and less than 400.

    Warning

    If you specify HTTPS for the value of Type , the endpoint must support TLS v1.0 or later.

    • TCP : Route 53 tries to establish a TCP connection.

    For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

  • ResourcePath (string) --

    The path that you want Route 53 to request when performing health checks. The path can be any value for which your endpoint will return an HTTP status code of 2xx or 3xx when the endpoint is healthy, such as the file /docs/route53-health-check.html . Route 53 automatically adds the DNS name for the service and a leading forward slash (/ ) character.

  • FailureThreshold (integer) --

    The number of consecutive health checks that an endpoint must pass or fail for Route 53 to change the current status of the endpoint from unhealthy to healthy or vice versa. For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

type HealthCheckCustomConfig

dict

param HealthCheckCustomConfig

  • FailureThreshold (integer) --

rtype

dict

returns

Response Syntax

{
    'Service': {
        'Id': 'string',
        'Arn': 'string',
        'Name': 'string',
        'Description': 'string',
        'InstanceCount': 123,
        'DnsConfig': {
            'NamespaceId': 'string',
            'RoutingPolicy': 'MULTIVALUE'|'WEIGHTED',
            'DnsRecords': [
                {
                    'Type': 'SRV'|'A'|'AAAA'|'CNAME',
                    'TTL': 123
                },
            ]
        },
        'HealthCheckConfig': {
            'Type': 'HTTP'|'HTTPS'|'TCP',
            'ResourcePath': 'string',
            'FailureThreshold': 123
        },
        'HealthCheckCustomConfig': {
            'FailureThreshold': 123
        },
        'CreateDate': datetime(2015, 1, 1),
        'CreatorRequestId': 'string'
    }
}

Response Structure

  • (dict) --

    • Service (dict) --

      A complex type that contains information about the new service.

      • Id (string) --

        The ID that Route 53 assigned to the service when you created it.

      • Arn (string) --

        The Amazon Resource Name (ARN) that Route 53 assigns to the service when you create it.

      • Name (string) --

        The name of the service.

      • Description (string) --

        The description of the service.

      • InstanceCount (integer) --

        The number of instances that are currently associated with the service. Instances that were previously associated with the service but that have been deleted are not included in the count.

      • DnsConfig (dict) --

        A complex type that contains information about the records that you want Route 53 to create when you register an instance.

        • NamespaceId (string) --

          The ID of the namespace to use for DNS configuration.

        • RoutingPolicy (string) --

          The routing policy that you want to apply to all records that Route 53 creates when you register an instance and specify this service.

          Note

          If you want to use this service to register instances that create alias records, specify WEIGHTED for the routing policy.

          You can specify the following values:

          MULTIVALUE

          If you define a health check for the service and the health check is healthy, Route 53 returns the applicable value for up to eight instances.

          For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with IP addresses for up to eight healthy instances. If fewer than eight instances are healthy, Route 53 responds to every DNS query with the IP addresses for all of the healthy instances.

          If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the values for up to eight instances.

          For more information about the multivalue routing policy, see Multivalue Answer Routing in the Route 53 Developer Guide .

          WEIGHTED

          Route 53 returns the applicable value from one randomly selected instance from among the instances that you registered using the same service. Currently, all records have the same weight, so you can't route more or less traffic to any instances.

          For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with the IP address for one randomly selected instance from among the healthy instances. If no instances are healthy, Route 53 responds to DNS queries as if all of the instances were healthy.

          If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the applicable value for one randomly selected instance.

          For more information about the weighted routing policy, see Weighted Routing in the Route 53 Developer Guide .

        • DnsRecords (list) --

          An array that contains one DnsRecord object for each record that you want Route 53 to create when you register an instance.

          • (dict) --

            A complex type that contains information about the records that you want Route 53 to create when you register an instance.

            • Type (string) --

              The type of the resource, which indicates the type of value that Route 53 returns in response to DNS queries.

              Note the following:

              • A, AAAA, and SRV records: You can specify settings for a maximum of one A, one AAAA, and one SRV record. You can specify them in any combination.

              • CNAME records: If you specify CNAME for Type , you can't define any other records. This is a limitation of DNS—you can't create a CNAME record and any other type of record that has the same name as a CNAME record.

              • Alias records: If you want Route 53 to create an alias record when you register an instance, specify A or AAAA for Type .

              • All records: You specify settings other than TTL and Type when you register an instance.

              The following values are supported:

              A

              Route 53 returns the IP address of the resource in IPv4 format, such as 192.0.2.44.

              AAAA

              Route 53 returns the IP address of the resource in IPv6 format, such as 2001:0db8:85a3:0000:0000:abcd:0001:2345.

              CNAME

              Route 53 returns the domain name of the resource, such as www.example.com. Note the following:

              • You specify the domain name that you want to route traffic to when you register an instance. For more information, see RegisterInstanceRequest$Attributes .

              • You must specify WEIGHTED for the value of RoutingPolicy .

              • You can't specify both CNAME for Type and settings for HealthCheckConfig . If you do, the request will fail with an InvalidInput error.

              SRV

              Route 53 returns the value for an SRV record. The value for an SRV record uses the following values:

              priority weight port service-hostname

              Note the following about the values:

              • The values of priority and weight are both set to 1 and can't be changed.

              • The value of port comes from the value that you specify for the AWS_INSTANCE_PORT attribute when you submit a RegisterInstance request.

              • The value of service-hostname is a concatenation of the following values:

                • The value that you specify for InstanceId when you register an instance.

                • The name of the service.

                • The name of the namespace.

              For example, if the value of InstanceId is test , the name of the service is backend , and the name of the namespace is example.com , the value of service-hostname is:

              test.backend.example.com

              If you specify settings for an SRV record and if you specify values for AWS_INSTANCE_IPV4 , AWS_INSTANCE_IPV6 , or both in the RegisterInstance request, Route 53 automatically creates A and/or AAAA records that have the same name as the value of service-hostname in the SRV record. You can ignore these records.

            • TTL (integer) --

              The amount of time, in seconds, that you want DNS resolvers to cache the settings for this record.

              Note

              Alias records don't include a TTL because Route 53 uses the TTL for the AWS resource that an alias record routes traffic to. If you include the AWS_ALIAS_DNS_NAME attribute when you submit a RegisterInstance request, the TTL value is ignored. Always specify a TTL for the service; you can use a service to register instances that create either alias or non-alias records.

      • HealthCheckConfig (dict) --

        Public DNS namespaces only. A complex type that contains settings for an optional health check. If you specify settings for a health check, Route 53 associates the health check with all the records that you specify in DnsConfig .

        For information about the charges for health checks, see Route 53 Pricing .

        • Type (string) --

          The type of health check that you want to create, which indicates how Route 53 determines whether an endpoint is healthy.

          Warning

          You can't change the value of Type after you create a health check.

          You can create the following types of health checks:

          • HTTP : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTP request and waits for an HTTP status code of 200 or greater and less than 400.

          • HTTPS : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTPS request and waits for an HTTP status code of 200 or greater and less than 400.

          Warning

          If you specify HTTPS for the value of Type , the endpoint must support TLS v1.0 or later.

          • TCP : Route 53 tries to establish a TCP connection.

          For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

        • ResourcePath (string) --

          The path that you want Route 53 to request when performing health checks. The path can be any value for which your endpoint will return an HTTP status code of 2xx or 3xx when the endpoint is healthy, such as the file /docs/route53-health-check.html . Route 53 automatically adds the DNS name for the service and a leading forward slash (/ ) character.

        • FailureThreshold (integer) --

          The number of consecutive health checks that an endpoint must pass or fail for Route 53 to change the current status of the endpoint from unhealthy to healthy or vice versa. For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

      • HealthCheckCustomConfig (dict) --

        • FailureThreshold (integer) --

      • CreateDate (datetime) --

        The date and time that the service was created, in Unix format and Coordinated Universal Time (UTC). The value of CreateDate is accurate to milliseconds. For example, the value 1516925490.087 represents Friday, January 26, 2018 12:11:30.087 AM.

      • CreatorRequestId (string) --

        A unique string that identifies the request and that allows failed requests to be retried without the risk of executing the operation twice. CreatorRequestId can be any unique string, for example, a date/time stamp.

GetService (updated) Link ¶
Changes (response) 
{'Service': {'HealthCheckCustomConfig': {'FailureThreshold': 'integer'}}}

Gets the settings for a specified service.

See also: AWS API Documentation

Request Syntax

client.get_service(
    Id='string'
)
type Id

string

param Id

[REQUIRED]

The ID of the service that you want to get settings for.

rtype

dict

returns

Response Syntax

{
    'Service': {
        'Id': 'string',
        'Arn': 'string',
        'Name': 'string',
        'Description': 'string',
        'InstanceCount': 123,
        'DnsConfig': {
            'NamespaceId': 'string',
            'RoutingPolicy': 'MULTIVALUE'|'WEIGHTED',
            'DnsRecords': [
                {
                    'Type': 'SRV'|'A'|'AAAA'|'CNAME',
                    'TTL': 123
                },
            ]
        },
        'HealthCheckConfig': {
            'Type': 'HTTP'|'HTTPS'|'TCP',
            'ResourcePath': 'string',
            'FailureThreshold': 123
        },
        'HealthCheckCustomConfig': {
            'FailureThreshold': 123
        },
        'CreateDate': datetime(2015, 1, 1),
        'CreatorRequestId': 'string'
    }
}

Response Structure

  • (dict) --

    • Service (dict) --

      A complex type that contains information about the service.

      • Id (string) --

        The ID that Route 53 assigned to the service when you created it.

      • Arn (string) --

        The Amazon Resource Name (ARN) that Route 53 assigns to the service when you create it.

      • Name (string) --

        The name of the service.

      • Description (string) --

        The description of the service.

      • InstanceCount (integer) --

        The number of instances that are currently associated with the service. Instances that were previously associated with the service but that have been deleted are not included in the count.

      • DnsConfig (dict) --

        A complex type that contains information about the records that you want Route 53 to create when you register an instance.

        • NamespaceId (string) --

          The ID of the namespace to use for DNS configuration.

        • RoutingPolicy (string) --

          The routing policy that you want to apply to all records that Route 53 creates when you register an instance and specify this service.

          Note

          If you want to use this service to register instances that create alias records, specify WEIGHTED for the routing policy.

          You can specify the following values:

          MULTIVALUE

          If you define a health check for the service and the health check is healthy, Route 53 returns the applicable value for up to eight instances.

          For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with IP addresses for up to eight healthy instances. If fewer than eight instances are healthy, Route 53 responds to every DNS query with the IP addresses for all of the healthy instances.

          If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the values for up to eight instances.

          For more information about the multivalue routing policy, see Multivalue Answer Routing in the Route 53 Developer Guide .

          WEIGHTED

          Route 53 returns the applicable value from one randomly selected instance from among the instances that you registered using the same service. Currently, all records have the same weight, so you can't route more or less traffic to any instances.

          For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with the IP address for one randomly selected instance from among the healthy instances. If no instances are healthy, Route 53 responds to DNS queries as if all of the instances were healthy.

          If you don't define a health check for the service, Route 53 assumes that all instances are healthy and returns the applicable value for one randomly selected instance.

          For more information about the weighted routing policy, see Weighted Routing in the Route 53 Developer Guide .

        • DnsRecords (list) --

          An array that contains one DnsRecord object for each record that you want Route 53 to create when you register an instance.

          • (dict) --

            A complex type that contains information about the records that you want Route 53 to create when you register an instance.

            • Type (string) --

              The type of the resource, which indicates the type of value that Route 53 returns in response to DNS queries.

              Note the following:

              • A, AAAA, and SRV records: You can specify settings for a maximum of one A, one AAAA, and one SRV record. You can specify them in any combination.

              • CNAME records: If you specify CNAME for Type , you can't define any other records. This is a limitation of DNS—you can't create a CNAME record and any other type of record that has the same name as a CNAME record.

              • Alias records: If you want Route 53 to create an alias record when you register an instance, specify A or AAAA for Type .

              • All records: You specify settings other than TTL and Type when you register an instance.

              The following values are supported:

              A

              Route 53 returns the IP address of the resource in IPv4 format, such as 192.0.2.44.

              AAAA

              Route 53 returns the IP address of the resource in IPv6 format, such as 2001:0db8:85a3:0000:0000:abcd:0001:2345.

              CNAME

              Route 53 returns the domain name of the resource, such as www.example.com. Note the following:

              • You specify the domain name that you want to route traffic to when you register an instance. For more information, see RegisterInstanceRequest$Attributes .

              • You must specify WEIGHTED for the value of RoutingPolicy .

              • You can't specify both CNAME for Type and settings for HealthCheckConfig . If you do, the request will fail with an InvalidInput error.

              SRV

              Route 53 returns the value for an SRV record. The value for an SRV record uses the following values:

              priority weight port service-hostname

              Note the following about the values:

              • The values of priority and weight are both set to 1 and can't be changed.

              • The value of port comes from the value that you specify for the AWS_INSTANCE_PORT attribute when you submit a RegisterInstance request.

              • The value of service-hostname is a concatenation of the following values:

                • The value that you specify for InstanceId when you register an instance.

                • The name of the service.

                • The name of the namespace.

              For example, if the value of InstanceId is test , the name of the service is backend , and the name of the namespace is example.com , the value of service-hostname is:

              test.backend.example.com

              If you specify settings for an SRV record and if you specify values for AWS_INSTANCE_IPV4 , AWS_INSTANCE_IPV6 , or both in the RegisterInstance request, Route 53 automatically creates A and/or AAAA records that have the same name as the value of service-hostname in the SRV record. You can ignore these records.

            • TTL (integer) --

              The amount of time, in seconds, that you want DNS resolvers to cache the settings for this record.

              Note

              Alias records don't include a TTL because Route 53 uses the TTL for the AWS resource that an alias record routes traffic to. If you include the AWS_ALIAS_DNS_NAME attribute when you submit a RegisterInstance request, the TTL value is ignored. Always specify a TTL for the service; you can use a service to register instances that create either alias or non-alias records.

      • HealthCheckConfig (dict) --

        Public DNS namespaces only. A complex type that contains settings for an optional health check. If you specify settings for a health check, Route 53 associates the health check with all the records that you specify in DnsConfig .

        For information about the charges for health checks, see Route 53 Pricing .

        • Type (string) --

          The type of health check that you want to create, which indicates how Route 53 determines whether an endpoint is healthy.

          Warning

          You can't change the value of Type after you create a health check.

          You can create the following types of health checks:

          • HTTP : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTP request and waits for an HTTP status code of 200 or greater and less than 400.

          • HTTPS : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTPS request and waits for an HTTP status code of 200 or greater and less than 400.

          Warning

          If you specify HTTPS for the value of Type , the endpoint must support TLS v1.0 or later.

          • TCP : Route 53 tries to establish a TCP connection.

          For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

        • ResourcePath (string) --

          The path that you want Route 53 to request when performing health checks. The path can be any value for which your endpoint will return an HTTP status code of 2xx or 3xx when the endpoint is healthy, such as the file /docs/route53-health-check.html . Route 53 automatically adds the DNS name for the service and a leading forward slash (/ ) character.

        • FailureThreshold (integer) --

          The number of consecutive health checks that an endpoint must pass or fail for Route 53 to change the current status of the endpoint from unhealthy to healthy or vice versa. For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

      • HealthCheckCustomConfig (dict) --

        • FailureThreshold (integer) --

      • CreateDate (datetime) --

        The date and time that the service was created, in Unix format and Coordinated Universal Time (UTC). The value of CreateDate is accurate to milliseconds. For example, the value 1516925490.087 represents Friday, January 26, 2018 12:11:30.087 AM.

      • CreatorRequestId (string) --

        A unique string that identifies the request and that allows failed requests to be retried without the risk of executing the operation twice. CreatorRequestId can be any unique string, for example, a date/time stamp.