后台调用_delete_by_query接口生成task时自动创建的.tasks映射爆红

1、elasticsearch-version:5.6.3
2、自动生成的mapping如图

 
3、我尝试了以下操作均无效：
   （1）修改auto_create_index为true之后，再执行创建后台任务的接口，自动生成的.tasks映射还是爆红-无效
   （2）修改routing.allocation.enable为all之后，再执行创建后台任务的接口，自动生成的.tasks映射还是爆红-无效

PUT /_cluster/settings/

{

    "persistent": {

        "cluster.routing.allocation.enable": "all",

        "action.auto_create_index": true

    }

}

4、集群参数设置如下

GET /_cluster/settings

{

    "persistent": {

        "action": {

            "auto_create_index": "false"

        },

        "cluster": {

            "routing": {

                "allocation": {

                    "enable": "none"

                }

            }

        }

    },

    "transient": {

        "cluster": {

            "routing": {

                "allocation": {

                    "enable": "none"

                }

            }

        },

        "logger": {

            "index": {

                "indexing": {

                    "slowlog": "INFO"

                },

                "search": {

                    "slowlog": "DEBUG"

                }

            }

        }

    }

}