如何知道 elasticsearch 安装成功了

要确保 Elasticsearch 安装成功，请按照以下步骤进行操作：

确认 Elasticsearch 运行状态。您可以使用以下命令来检查 Elasticsearch 是否正在运行：

$ sudo systemctl status elasticsearch

如果 Elasticsearch 正在运行，您将看到类似于以下内容的输出：

● elasticsearch.service - Elasticsearch
   Loaded: loaded (/usr/lib/systemd/system/elasticsearch.service; enabled; vendor preset: disabled)
   Active: active (running) since Wed 2019-01-02 14:06:59 UTC; 24h ago
     Docs: http://www.elastic.co
 Main PID: 12756 (java)
   CGroup: /system.slice/elasticsearch.service
           └─12756 /usr/bin/java -Xms2g -Xmx2g -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -Des.network.host=_ec2:ipv4_

测试 Elasticsearch 是否可以响应。您可以使用以下命令来测试 Elasticsearch 是否响应：

$ curl -XGET 'localhost:9200/?pretty'

如果 Elasticsearch 正在运行，您将看到类似于以下内容的输出：

{
  "name" : "Your Node Name",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "x7k4zE3lT5O5ZSd8xwYtIA",
  "version" : {
    "number" : "7.9.3",
    "build_flavor" : "default",
    "build_type" : "rpm",
    "build_hash" : "c4138e51121ef06a6404866cddc601906fe5c868",
    "build_date" : "2020-10-16T10:36:16.141335Z",
    "build_snapshot" : false,
    "lucene_version" : "8.6.2",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  },
  "tagline" : "You Know, for Search"
}

如果您可以看到 Elasticsearch 的版本信息，则说明 Elasticsearch 已经成功安装并且正在运行