keystone/api-ref/source/v3/samples/admin/domain-config-create-request.json

{
    "config": {
        "identity": {
            "driver": "ldap"
        },
        "ldap": {
            "url": "ldap://myldap.com:389/",
            "user_tree_dn": "ou=Users,dc=my_new_root,dc=org"
        }
    }
}