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Cloud Enterprise Network:CreateTransitRouterMulticastDomain

Last Updated:Jul 15, 2026

Creates a multicast domain. A multicast domain defines the scope of a multicast network within a region. Only resources within the multicast domain can send and receive multicast traffic. Resources outside the multicast domain cannot send or receive multicast traffic.

Operation description

Before you call this operation, take note of the following information:

  • Make sure that you have created an Enterprise Edition transit router in the region where you want to establish a multicast network and that the multicast feature is enabled for the Enterprise Edition transit router. For more information, see CreateTransitRouter.

    If you created an Enterprise Edition transit router instance before you applied for multicast resources, the Enterprise Edition transit router instance does not support the multicast feature. You can delete the current Enterprise Edition transit router instance and create a new one. For information about how to delete an Enterprise Edition transit router instance, see DeleteTransitRouter.

  • When you call the CreateTransitRouterMulticastDomain operation, if you specify the CenId and RegionId parameters, you do not need to specify the TransitRouterId parameter. If you specify the TransitRouterId parameter, you do not need to specify the CenId or RegionId parameters.

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Test

RAM authorization

The table below describes the authorization required to call this API. You can define it in a Resource Access Management (RAM) policy. The table's columns are detailed below:

  • Action: The actions can be used in the Action element of RAM permission policy statements to grant permissions to perform the operation.

  • API: The API that you can call to perform the action.

  • Access level: The predefined level of access granted for each API. Valid values: create, list, get, update, and delete.

  • Resource type: The type of the resource that supports authorization to perform the action. It indicates if the action supports resource-level permission. The specified resource must be compatible with the action. Otherwise, the policy will be ineffective.

    • For APIs with resource-level permissions, required resource types are marked with an asterisk (*). Specify the corresponding Alibaba Cloud Resource Name (ARN) in the Resource element of the policy.

    • For APIs without resource-level permissions, it is shown as All Resources. Use an asterisk (*) in the Resource element of the policy.

  • Condition key: The condition keys defined by the service. The key allows for granular control, applying to either actions alone or actions associated with specific resources. In addition to service-specific condition keys, Alibaba Cloud provides a set of common condition keys applicable across all RAM-supported services.

  • Dependent action: The dependent actions required to run the action. To complete the action, the RAM user or the RAM role must have the permissions to perform all dependent actions.

Action

Access level

Resource type

Condition key

Dependent action

cen:CreateTransitRouterMulticastDomain

create

TransitRouter

acs:cen:*:{#accountId}:centransitrouter/{#centransitrouterId}

*TransitRouterMulticastDomain

acs:cen:*:{#accountId}:centransitroutermulticast/*

None None

Request parameters

Parameter

Type

Required

Description

Example

ClientToken

string

No

The client token that is used to ensure the idempotence of the request.

You can use the client to generate the token, but you must make sure that the token is unique among different requests. The token can contain only ASCII characters.

123e4567-e89b-12d3-a456-4266****

CenId

string

No

The instance ID of the Cloud Enterprise Network (CEN).

cen-a7syd349kne38g****

TransitRouterId

string

No

The instance ID of the transit router.

tr-p0wr9p28r92d598y6****

RegionId

string

No

The region ID of the transit router instance.

You can call the DescribeChildInstanceRegions operation to query the region ID.

cn-hangzhou

TransitRouterMulticastDomainName

string

No

The name of the multicast domain.

The name can be empty or 1 to 128 characters in length, and cannot start with http:// or https://.

nametest

TransitRouterMulticastDomainDescription

string

No

The description of the multicast domain.

The description can be empty or 1 to 256 characters in length, and cannot start with http:// or https://.

desctest

DryRun

boolean

No

Specifies whether to perform a dry run. Valid values:

  • true: performs a dry run. The system checks the required parameters, request syntax, and limits. If the request fails the dry run, an error message is returned. If the request passes the dry run, the DryRunOperation error code is returned.

  • false (default): performs a dry run and sends the request. If the request passes the dry run, the multicast domain is created.

false

Tag

array<object>

No

The tag information.

You can specify up to 20 tags at a time.

object

No

Key

string

No

The tag key of the resource.

Once you specify this parameter, it cannot be an empty string. The tag key can be up to 64 characters in length and cannot start with aliyun or acs:. It cannot contain http:// or https://.

You can specify up to 20 tag keys at a time.

TagKey

Value

string

No

The tag value of the resource.

The tag value can be empty or up to 128 characters in length. It cannot start with aliyun or acs:, and cannot contain http:// or https://.

Each tag key corresponds to one tag value. You can specify up to 20 tag values at a time.

TagValue

Options

object

No

The feature options of the multicast domain.

Igmpv2Support

string

No

Specifies whether to enable the Internet Group Management Protocol (IGMP) feature for the multicast domain. After this feature is enabled, hosts can dynamically join or leave multicast groups by using the IGMP protocol. Valid values:

  • enable: enables the IGMP feature.

  • disable (default): disables the IGMP feature.

Note
  • The IGMP feature is in public preview. To use this feature, contact your account manager to apply for permissions.

  • After the IGMP feature is enabled, it cannot be disabled.

enable

StrictSourceControl

string

No

Specifies whether to enable the strict multicast source control feature. If this feature is disabled, all ECS instances associated with the vSwitch can serve as multicast sources. If this feature is enabled, only ENIs that are statically configured or that have sent IGMP Join messages can serve as multicast sources. Valid values:

  • enable: enables the strict multicast source control feature.

  • disable: disables the strict multicast source control feature.

Note
  • The strict multicast source control feature takes effect only for multicast domains with the IGMP feature enabled.

  • You can create only one multicast domain with the strict multicast source control feature disabled for each transit router.

enable

Response elements

Element

Type

Description

Example

object

The response struct.

TransitRouterMulticastDomainId

string

The ID of the multicast domain.

tr-mcast-domain-40cwj0rgzgdtam****

RequestId

string

The request ID.

94E19C6F-206F-5223-9A63-64B85851BC04

Examples

Success response

JSON format

{
  "TransitRouterMulticastDomainId": "tr-mcast-domain-40cwj0rgzgdtam****",
  "RequestId": "94E19C6F-206F-5223-9A63-64B85851BC04"
}

Error codes

HTTP status code

Error code

Error message

Description

400 InvalidTransitRouterId.NotFound The specified TransitRouterId is not found. The error message returned because the specified transit router ID (TransitRouterId) does not exist.
400 IllegalParam.TransitRouterId The specified TransitRouterId is illegal. The error message returned because the specified transit router ID is invalid.
400 IllegalParam.CenId The specified CenId is illegal. The error message returned because the specified CEN instance ID is invalid.
400 IllegalParam.RegionId The specified RegionId is illegal. The error message returned because the specified region is invalid.
400 InvalidCenId.NotFound The specified CenId is not found. The error message returned because the specified CEN instance ID does not exist.
400 InvalidOperation.TransitRouterNotExist Operation is invalid because the transit router not exist. The error message returned because the specified transit router does not exist.
400 InvalidOperation.CENInstanceStatus The CEN instance is not in a valid state for the operation.
400 IncorrectStatus.TransitRouterInstance The status of TransitRouter is incorrect. The error message returned because the transit router is in an invalid state.
400 OperationUnsupported.TransitRouterType The specified TransitRouterType does not support the operation. The error message returned because this operation is not supported by the specified type of transit router.
400 OperationUnsupported.ServiceMode The specified ServiceMode does not support the operation. The error message returned because the transit router mode does not support this operation.
400 OperationUnsupported.TransitRouterSupportMulticast The specified TransitRouterSupportMulticast does not support the operation.
400 OperationUnsupported.RegionId The specified RegionId does not support the operation. The error message returned because this operation is not supported in the specified region.
400 IncorrectStatus.Cen The status of Cen is incorrect. The error message returned because the status of the specified CEN instance does not support this operation. Try again later.
400 IncorrectStatus.TransitRouter The status of TransitRouter is incorrect. The error message returned because the status of the transit router does not support this operation. Try again later.
400 DryRunOperation Request validation has been passed with DryRun flag set. The error message returned because the dry run request passed the precheck.
400 QuotaExceeded.MulticastDomain The MulticastDomain quota is exceeded. The error message returned because the number of multicast domains has reached the upper limit. You cannot add more multicast domains.
400 IllegalParam.Igmpv2Support The specified Igmpv2Support is illegal. Valid values are [enable, disable]. The parameter Igmpv2Support is invalid. Value range: enable, disable.
400 OperationUnsupported.Igmpv2Support The current UID does not allow the creation of a igmpv2 multicast domain. Please submit a ticket. The current UID does not allow the creation of a multicast domain of the igmpv2 type. Please submit a ticket.
400 InvalidParameter Invalid parameter. The error message returned because the parameter is set to an invalid value.
400 Unauthorized The AccessKeyId is unauthorized. The error message returned because you do not have the permissions to perform this operation.
400 InvalidParameter.TagValue The specified parameter TagValue is invalid. The input parameter Tag Value is invalid.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.