在我的开发环境中，我可以创建一个elasticsearch索引，该索引具有一个别名数据类型的属性。然而，在aws（elasticsearch服务）中，当我尝试相同的操作时，它失败了。
我的dev elasticsearch版本：6.4.2
aws elasticsearch版本：6.3.1
我正在尝试使用elasticsearch网站的示例代码：https://www.elastic.co/guide/en/elasticsearch/reference/current/alias.html

PUT trips
{
    "mappings": {
        "_doc": {
            "properties": {
                "distance": {
                    "type": "long"
                },
                "route_length_miles": {
                    "type": "alias",
                    "path": "distance"
                },
                "transit_mode": {
                    "type": "keyword"
                }
            }
        }
    }
}

我得到的是：

{
    "error": {
        "root_cause": [
            {
                "type": "mapper_parsing_exception",
                "reason": "No handler for type [alias] declared on field [route_length_miles]"
            }
        ],
        "type": "mapper_parsing_exception",
        "reason": "Failed to parse mapping [_doc]: No handler for type [alias] declared on field [route_length_miles]",
        "caused_by": {
            "type": "mapper_parsing_exception",
            "reason": "No handler for type [alias] declared on field [route_length_miles]"
        }
    },
    "status": 400
}