elsticsearch在配置IK分词插件报错，请问怎么处理？

/*
大佬们，在Linux 配置 es的IK插件时报这样的错误，是什么原因？这个也是根据GitHub上配置的，
这是配置：
curl -XPOST http://192.168.117.8:9200/index2/create/_mapping -H 'Content-Type:application/json' -d'{

    "properties": {
        "content": {
            "type": "text",
            "analyzer": "ik_max_word",
            "search_analyzer": "ik_smart"
        }
    }

}'
然后报下面的错误信息：
"error":{"root_cause":[{"type":"action_request_validation_exception","reason":"Validation Failed: 1: mapping type is missing;"}],
"type":"action_request_validation_exception","reason":"Validation Failed: 1: mapping type is missing;"},"status":400}

https://blog.csdn.net/zhanlanmg/article/details/48729443

Elasticsearch For .Net项目实战
https://www.52interview.com/book/1/5