[root@localhost bin]# ./elasticsearch -d
[root@localhost bin]# Exception in thread "main" java.lang.RuntimeException: don't run elasticsearch as root.
	at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:93)
	at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:144)
	at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:285)
	at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:35)
Refer to the log for complete error details.
创建elk用户：elk:x:500:500::/home/elk:/bin/bash
赋予权限：
 
[root@localhost opt]# chown -R elk.elk elasticsearch-2.2.1
切换elk帐户：
 
[root@localhost elasticsearch-2.2.1]# su elk
启动elasticsearch:
 
[elk@localhost bin]$ ./elasticsearch -d
检查是否启动：[elk@localhost bin]$ curl -XGxt http://localhost:9200/
{
  "name" : "Iron Man",
  "cluster_name" : "elasticsearch",
  "version" : {
    "number" : "2.2.1",
    "build_hash" : "d045fc29d1932bce18b2e65ab8b297fbf6cd41a1",
    "build_timestamp" : "2016-03-09T09:38:54Z",
    "build_snapshot" : false,
    "lucene_version" : "5.4.1"
  },
  "tagline" : "You Know, for Search"
}