# AWS::Amplify::Domain SubDomainSetting ## Syntax To declare this entity in your AWS CloudFormation template, use the following syntax: ### JSON
{ "Prefix" : String, "BranchName" : String }### YAML
Prefix: String BranchName: String## Properties #### Prefix _Required_: Yes _Type_: String _Maximum_:
255
_Pattern_: (?s).*
_Update requires_: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)
#### BranchName
_Required_: Yes
_Type_: String
_Minimum_: 1
_Maximum_: 255
_Pattern_: (?s).+
_Update requires_: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)