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    Anti-DDoS:ConfigUdpReflect

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    Anti-DDoS:ConfigUdpReflect

    Last Updated:Feb 25, 2026

    Adds the filtering policies for UDP reflection attacks on an Anti-DDoS Pro or Anti-DDoS Premium instance to filter out the source ports of UDP traffic.

    Operation description

    You can call this operation to configure filtering policies to filter out UDP traffic from specific ports. This helps defend against UDP reflection attacks.

    Limits

    You can call this operation up to 10 times per second per account. If the number of the calls per second exceeds the limit, throttling is triggered. As a result, your business may be affected. We recommend that you take note of the limit when you call this operation.

    Try it now

    Try this API in OpenAPI Explorer, no manual signing needed. Successful calls auto-generate SDK code matching your parameters. Download it with built-in credential security for local usage.

    Test

    RAM authorization

    No authorization for this operation. If you encounter issues with this operation, contact technical support.

    Request parameters

    Parameter

    Type

    Required

    Description

    Example
    InstanceId

    string

    Yes

    The ID of the instance.

    Note

    You can call the DescribeInstanceIds operation to query the IDs of all instances.

    ddoscoo-cn-i7m25564****
    Config

    string

    Yes

    The configuration of the filtering policy for UDP reflection attacks.

    The value is a string that consists of a JSON struct. The JSON struct contains the following field:

    • UdpSports: the source ports of the UDP traffic that you want to block. This field is required and must be of the ARRAY type. Example: [17,19].

      We recommend that you block the following source ports of UDP traffic:

      • UDP 17: QOTD reflection attacks

      • UDP 19: CharGEN reflection attacks

      • UDP 69: TFTP reflection attacks

      • UDP 111: Portmap reflection attacks

      • UDP 123: NTP reflection attacks

      • UDP 137: NetBIOS reflection attacks

      • UDP 161: SNMPv2 reflection attacks

      • UDP 389: CLDAP reflection attacks

      • UDP 1194: OpenVPN reflection attacks

      • UDP 1900: SSDP reflection attacks

      • UDP 3389: RDP reflection attacks

      • UDP 11211: memcached reflection attacks

    {\"UdpSports\":[17,19]}
    RegionId

    string

    No

    The region ID of the Anti-DDoS Proxy instance. Valid values:

    • cn-hangzhou: indicates an Anti-DDoS Proxy (Chinese Mainland) instance. This is the default value.

    • ap-southeast-1: indicates an Anti-DDoS Proxy (Outside Chinese Mainland) instance.

    cn-hangzhou

    All Alibaba Cloud API operations must include common request parameters. For more information about common request parameters, see Common parameters.

    For more information about sample requests, see the "Examples" section of this topic.

    Response elements

    Element

    Type

    Description

    Example

    object

    RequestId

    string

    The ID of the request.

    9EC62E89-BD30-4FCD-9CB8-FA53865FF0D7

    Examples

    Success response

    JSON format

    {
  "RequestId": "9EC62E89-BD30-4FCD-9CB8-FA53865FF0D7"
}

    Error codes

    See Error Codes for a complete list.

    Release notes

    See Release Notes for a complete list.