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此篇文章用于收纳安装elasticsearch后启动遇到的一些问题。
文章目录
问题1：can not run elasticsearch as root
直接用root用户启动会出现如下类似的错误：
root@cc-server:/home/environment/elasticsearch-6.4.2# ./bin/elasticsearch
[2018-10-11T18:37:43,323][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [] 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:140) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:127) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.4.2.jar:6.4.2]
at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:93) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:86) ~[elasticsearch-6.4.2.jar:6.4.2]
Caused by: java.lang.RuntimeException: can not run elasticsearch as root
at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:104) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:171) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:326) ~[elasticsearch-6.4.2.jar:6.4.2]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:136) ~[elasticsearch-6.4.2.jar:6.4.2]
... 6 more
解决办法：
//添加用户
adduser elasticsearch
//为用户赋值权限目录
//chown -R [用户][所属组] 文件夹目录
chown -R elasticsearch:elasticsearch elasticsearch-6.4.2/
问题2：max file descriptors for elasticsearch process is too low
在es启动时可能出现类似ERROR信息如下：
max file descriptors [65535] for elasticsearch process is too low, increase to at least [65536]
解决办法：
修改文件/etc/security/limits.conf
vim /etc/security/limits.conf
添加如下配置,配置值设为需要的值即可：
#<domain> <type> <item> <value>
#四个元素的意义在该文件中均有详细描述
elasticsearch soft nofile 65536
elasticsearch hard nofile 65536
问题3：max virtual memory areas vm.max_map_count is too low
在es启动时可能出现类似ERROR信息如下：
max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
解决办法：
root权限下修改/etc/sysctl.conf文件，
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vim /etc/sysctl.conf
添加如下配置，配置值设为需要的值即可
vm.max_map_count=655360
然后执行如下命令
sysctl -p
问题4：failed to send join request to master
在es启动时可能出现ERROR信息如下：
failed to send join request to master.can't add node found existing node with the same id but is a different node instance.
分析：
如果es的data存储路径在es文件夹下，在拷贝已被启动过的es文件夹的时候，data路径下已生成了节点的信息。所以只需要删除配置的data路径下的东西即可。