用的騰訊雲服務器：
1. 進入控制台 --> 安全組 --> 添加規則 ， 開放9200端口
2. 配置/usr/local/es/elasticsearch-5.5.2/config/ 路徑下的 elasticsearch.yml
http.host: 0.0.0.0 http.port: 9200
糾正：http.host: 0.0.0.0 后來改成了 --》network.host: 0.0.0.0
bash /usr/local/es/elasticsearch-5.5.2/bin/elasticsearch -d
{
"name" : "QHNWXbg",
"cluster_name" : "elasticsearch",
"cluster_uuid" : "hVyq1z2LR9aEiyBhEsU-fw",
"version" : {
"number" : "5.5.2",
"build_hash" : "b2f0c09",
"build_date" : "2017-08-14T12:33:14.154Z",
"build_snapshot" : false,
"lucene_version" : "6.6.0"
},
"tagline" : "You Know, for Search"
}