setIdentifier

Resource record sets that have a routing policy other than simple: An identifier that differentiates among multiple resource record sets that have the same combination of name and type, such as multiple weighted resource record sets named acme.example.com that have a type of A. In a group of resource record sets that have the same name and type, the value of SetIdentifier must be unique for each resource record set.

For information about routing policies, see Choosing a Routing Policy in the Amazon Route 53 Developer Guide.