ela安装过程中的坑

1.用户权限的问题

[2020-07-03T17:06:30,735][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [node-1] 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-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:150) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-7.3.2.jar:7.3.2] at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:115) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:92) ~[elasticsearch-7.3.2.jar:7.3.2] Caused by: java.lang.RuntimeException: can not run elasticsearch as root at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:105) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:172) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:349) ~[elasticsearch-7.3.2.jar:7.3.2] at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:159) ~[elasticsearch-7.3.2.jar:7.3.2] ... 6 more 出现这种错误是因为ela为了系统的安全，不允许使用root启动，应切换到普通用户启动

2.内存问题

Exception in thread "main" java.lang.RuntimeException: starting java failed with [1] output: # # There is insufficient memory for the Java Runtime Environment to continue. # Native memory allocation (mmap) failed to map 8502706176 bytes for committing reserved memory. # An error report file with more information is saved as: # logs/hs_err_pid1887.log

出现这个问题是因为默认分配的jvm空间是2g，而虚拟机是1核2g，所以在启动的时候报了内存分配的错误

修改一下jvm.options

[root@localhost elasticsearch-7.3.2] vi config/jvm.options

改为 如果不行再改小点

3.出现max file descriptors [65535] for elasticsearch process is too low, increase to at least [65536]错误

在root下，修改/etc/security/limits.conf文件配置

vim /etc/security/limits.conf //在后面加上 * soft nofile 65536 * hard nofile 65536

4.出现max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]错误

再root下修改/etc/sysctl.conf

vi /etc/sysctl.conf //在后面加上 vm.max_map_count=655360

保存退出，执行sysctl -p

然后切换回普通用户，重新启动