reason": "Root mapping definition has unsupported parameters:

1、在Kibana创建索引的时候报错，使用的elasticsearch版本是7.2.1版本。

PUT /person
{
  "settings": {
    "number_of_shards": "10",
    "number_of_replicas": "0",
    "refresh_interval": "-1"
  },
  "mappings": {
    "properties": {
      "update_time": {
        "format": "yyyy-MM-dd HH:mm:ss",
        "type": "date"
      },
      "username": {
        "type": "keyword"
      },
      "address": {
        "type": "keyword"
      }
    }
  }
}

　　报错，如下所示：

{
    "error": {
        "root_cause": [{
            "type": "mapper_parsing_exception",
            "reason": "Root mapping definition has unsupported parameters:  [project_evaluate : {properties={update_time={format=yyyy-MM-dd HH:mm:ss, type=date}, username={type=keyword}, address={type=keyword}}}]"
        }],
        "type": "mapper_parsing_exception",
        "reason": "Failed to parse mapping [_doc]: Root mapping definition has unsupported parameters:  [project_evaluate : {properties={update_time={format=yyyy-MM-dd HH:mm:ss, type=date}, username={type=keyword}, address={type=keyword}}}]",
        "caused_by": {
            "type": "mapper_parsing_exception",
            "reason": "Root mapping definition has unsupported parameters:  [project_evaluate : {properties={update_time={format=yyyy-MM-dd HH:mm:ss, type=date}, username={type=keyword}, address={type=keyword}}}]"
        }
    },
    "status": 400
}

　　具体原因是ElasticSearch 7.x 默认不在支持指定索引类型。所以在ElasticSearch 7.x中不指定索引类型，创建索引是成功的。

　　但是对于ElasticSearch 6.x执行时没有问题的，Elasticsearch7默认不在支持指定索引类型，默认索引类型是_doc，索引不再推荐创建索引类型了，使用默认的即可。因为elasticsearch8后就不在提供该字段。