【原创】《从0开始学Elasticsearch》—初识Elasticsearch (2)

再次启动 Elasticsearch：

[root@153-215 elasticsearch-6.6.0]# bin/elasticsearch
[2019-02-13T16:42:53,177][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [unknown] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.RuntimeException: can not run elasticsearch as root
        at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:163) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:150) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.6.0.jar:6.6.0]
        at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:116) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:93) ~[elasticsearch-6.6.0.jar:6.6.0]
Caused by: java.lang.RuntimeException: can not run elasticsearch as root
        at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:103) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:170) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:333) ~[elasticsearch-6.6.0.jar:6.6.0]
        at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:159) ~[elasticsearch-6.6.0.jar:6.6.0]
        ... 6 more

这段报错信息也就是说，不能以 root 用户的身份启动 Elasticsearch，这一要求也是出于系统安全考虑，所以此处我先将 Elasticsearch 目录及目录内文件的拥有者修改为另一个用户，然后再用另一个用户启动：

[root@153-215 elasticsearch-6.6.0]# cd ..
[root@153-215 local]# chown -R lilinru:lilinru elasticsearch-6.6.0
[root@153-215 local]# su lilinru
[lilinru@153-215 local]$ cd elasticsearch-6.6.0
[lilinru@153-215 elasticsearch-6.6.0]$ bin/elasticsearch
....
[2019-02-13T17:10:23,443][INFO ][o.e.n.Node               ] [_xV7bTf] starting ...
[2019-02-13T17:10:23,618][INFO ][o.e.t.TransportService   ] [_xV7bTf] publish_address {127.0.0.1:9300}, bound_addresses {127.0.0.1:9300}
[2019-02-13T17:10:23,636][WARN ][o.e.b.BootstrapChecks    ] [_xV7bTf] max file descriptors [65535] for elasticsearch process is too low, increase to at least [65536]
[2019-02-13T17:10:23,636][WARN ][o.e.b.BootstrapChecks    ] [_xV7bTf] max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
....