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摘要
本文主要梳理从ES初学以来所遇到的启动失败的几种情况。
1、使用root用户启动失败
在有一次搭建elasticsearch的时候，使用systemctl启动elasticsearch失败，然后在bin目录下面去使用启动脚本启动，发现报错不能用root用户启动，报"Caused by: java.lang.RuntimeException: can not run elasticsearch as root"：
[root@localhost bin]# ./elasticsearch
[2017-12-20T17:01:47,922][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:125) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:112) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.1.1.jar:6.1.1]
at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:92) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:85) ~[elasticsearch-6.1.1.jar:6.1.1]
Caused by: java.lang.RuntimeException: can not run elasticsearch as root
at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:104) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:171) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:322) ~[elasticsearch-6.1.1.jar:6.1.1]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:121) ~[elasticsearch-6.1.1.jar:6.1.1]
... 6 more
[root@localhost bin]# cd ..
解决：
创建一个独立的用户，比如elk来启动elasticsearch，不用root用户启动
2、elasticsearch安装目录权限不对
遇到启动elasticsearch失败，使用的是专门的用户elk来启动的，启动日志提示不能加载配置文件：
[elk@docker bin]$ ./elasticsearch
Exception in thread "main" 2018-06-03 17:36:23,881 main ERROR No log4j2 configuration file found. Using default configuration: logging only errors to the console. Set system property 'log4j2.debug' to show Log4j2 internal initialization logging.
2018-06-03 17:36:24,113 main ERROR Could not register mbeans java.security.AccessControlException: access denied ("javax.management.MBeanTrustPermission" "register")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:472)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:585)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.checkMBeanTrustPermission(DefaultMBeanServerInterceptor.java:1848)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:322)
at com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:522)
at org.apache.logging.log4j.core.jmx.Server.register(Server.java:389)
at org.apache.logging.log4j.core.jmx.Server.reregisterMBeansAfterReconfigure(Server.java:167)
at org.apache.logging.log4j.core.jmx.Server.reregisterMBeansAfterReconfigure(Server.java:140)
at org.apache.logging.log4j.core.LoggerContext.setConfiguration(LoggerContext.java:556)
at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:617)
at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:634)
at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:229)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:242)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:45)
at org.apache.logging.log4j.LogManager.getContext(LogManager.java:174)
at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:618)
at org.elasticsearch.common.logging.ESLoggerFactory.getLogger(ESLoggerFactory.java:54)
at org.elasticsearch.common.logging.ESLoggerFactory.getLogger(ESLoggerFactory.java:62)
at org.elasticsearch.common.logging.Loggers.getLogger(Loggers.java:101)
at org.elasticsearch.ExceptionsHelper.<clinit>(ExceptionsHelper.java:42)
at org.elasticsearch.ElasticsearchException.toString(ElasticsearchException.java:663)
at java.lang.String.valueOf(String.java:2994)
at java.io.PrintStream.println(PrintStream.java:821)
at java.lang.Throwable$WrappedPrintStream.println(Throwable.java:748)
at java.lang.Throwable.printStackTrace(Throwable.java:655)
at java.lang.Throwable.printStackTrace(Throwable.java:643)
at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1061)
at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1052)
at java.lang.Thread.dispatchUncaughtException(Thread.java:1959)
SettingsException[Failed to load settings from /usr/local/elasticsearch-5.6.0/config/elasticsearch.yml]; nested: AccessDeniedException[/usr/local/elasticsearch-5.6.0/config/elasticsearch.yml];
at org.elasticsearch.node.InternalSettingsPreparer.prepareEnvironment(InternalSettingsPreparer.java:102)
at org.elasticsearch.cli.EnvironmentAwareCommand.createEnv(EnvironmentAwareCommand.java:72)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:67)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84)
Caused by: java.nio.file.AccessDeniedException: /usr/local/elasticsearch-5.6.0/config/elasticsearch.yml
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)
at sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:214)
at java.nio.file.Files.newByteChannel(Files.java:361)
at java.nio.file.Files.newByteChannel(Files.java:407)
at java.nio.file.spi.FileSystemProvider.newInputStream(FileSystemProvider.java:384)
at java.nio.file.Files.newInputStream(Files.java:152)
at org.elasticsearch.common.settings.Settings$Builder.loadFromPath(Settings.java:1032)
at org.elasticsearch.node.InternalSettingsPreparer.prepareEnvironment(InternalSettingsPreparer.java:100)
... 6 more
[elk@docker bin]$
解决：
看到"Caused by: java.nio.file.AccessDeniedException: /usr/local/elasticsearch-5.6.0/config/elasticsearch.yml"的提示，就去检查目录的权限，果然是root:root权限，使用elk用户去启动，就报错了。
将目录的权限改成elk:elk就好了。
[root@docker ~]# ll /usr/local/
drwxr-xr-x 7 root root 123 9月 7 2017 elasticsearch-5.6.0
[root@docker local]# chown -R elk:elk elasticsearch-5.6.0
[root@docker local]# ll
drwxr-xr-x 7 elk elk 123 9月 7 2017 elasticsearch-5.6.0
3、使用yum安装方式，赋权错误，启动失败
在一次使用yum安装elasticsearch的时候，执行完yum -y install elasticsearch 命令后，进行了下面的操作：
1、修改elasticsearch.yml文件
2、创建elk用户
3、创建/opt/elk/data目录，并且赋权为elk:elk
4、修改/var/log/elasticsearch权限为elk:elk
5、启动服务，但是报下面的错（截取了部分）：
[root@test101 init.d]# ./elasticsearch start
Starting elasticsearch: 2018-06-12 15:13:50,287 main ERROR Unable to create file /var/log/elasticsearch/elk.log java.io.IOException: 权限不够
at java.io.UnixFileSystem.createFileExclusively(Native Method)
at java.io.File.createNewFile(File.java:1012)
at org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory.createManager(RollingFileManager.java:628)
at org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory.createManager(RollingFileManager.java:608)
at org.apache.logging.log4j.core.appender.AbstractManager.getManager(AbstractManager.java:113)
at org.apache.logging.log4j.core.appender.OutputStreamManager.getManager(OutputStreamManager.java:115)
at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.getFileManager(RollingFileManager.java:188)
at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:144)
at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:60)
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.build(PluginBuilder.java:122)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createPluginObject(AbstractConfiguration.java:958)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:898)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:890)
at org.apache.logging.log4j.core.config.AbstractConfiguration.doConfigure(AbstractConfiguration.java:513)
at org.apache.logging.log4j.core.config.AbstractConfiguration.initialize(AbstractConfiguration.java:237)
at org.apache.logging.log4j.core.config.AbstractConfiguration.start(AbstractConfiguration.java:249)
at org.apache.logging.log4j.core.LoggerContext.setConfiguration(LoggerContext.java:545)
at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:261)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:166)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:122)
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:307)
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132)
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:123)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:70)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84)
2018-06-12 15:13:50,296 main ERROR Could not create plugin of type class org.apache.logging.log4j.core.appender.RollingFileAppender for element RollingFile: java.lang.IllegalStateException: ManagerFactory [org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory@16293aa2] unable to create manager for [/var/log/elasticsearch/elk.log] with data [org.apache.logging.log4j.core.appender.rolling.RollingFileManager$FactoryData@5158b42f[pattern=/var/log/elasticsearch/elk-%d{yyyy-MM-dd}.log, append=true, bufferedIO=true, bufferSize=8192, policy=CompositeTriggeringPolicy(policies=[TimeBasedTriggeringPolicy(nextRolloverMillis=0, interval=1, modulate=true)]), strategy=DefaultRolloverStrategy(min=1, max=7, useMax=true), advertiseURI=null, layout=[%d{ISO8601}][%-5p][%-25c{1.}] %marker%.-10000m%n, filePermissions=null, fileOwner=null]] java.lang.IllegalStateException: ManagerFactory [org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory@16293aa2] unable to create manager for [/var/log/elasticsearch/elk.log] with data [org.apache.logging.log4j.core.appender.rolling.RollingFileManager$FactoryData@5158b42f[pattern=/var/log/elasticsearch/elk-%d{yyyy-MM-dd}.log, append=true, bufferedIO=true, bufferSize=8192, policy=CompositeTriggeringPolicy(policies=[TimeBasedTriggeringPolicy(nextRolloverMillis=0, interval=1, modulate=true)]), strategy=DefaultRolloverStrategy(min=1, max=7, useMax=true), advertiseURI=null, layout=[%d{ISO8601}][%-5p][%-25c{1.}] %marker%.-10000m%n, filePermissions=null, fileOwner=null]]
at org.apache.logging.log4j.core.appender.AbstractManager.getManager(AbstractManager.java:115)
at org.apache.logging.log4j.core.appender.OutputStreamManager.getManager(OutputStreamManager.java:115)
at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.getFileManager(RollingFileManager.java:188)
at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:144)
at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:60)
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.build(PluginBuilder.java:122)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createPluginObject(AbstractConfiguration.java:958)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:898)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:890)
at org.apache.logging.log4j.core.config.AbstractConfiguration.doConfigure(AbstractConfiguration.java:513)
at org.apache.logging.log4j.core.config.AbstractConfiguration.initialize(AbstractConfiguration.java:237)
at org.apache.logging.log4j.core.config.AbstractConfiguration.start(AbstractConfiguration.java:249)
at org.apache.logging.log4j.core.LoggerContext.setConfiguration(LoggerContext.java:545)
at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:261)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:166)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:122)
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:307)
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132)
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:123)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:70)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84)
2018-06-12 15:13:50,311 main ERROR Unable to invoke factory method in class org.apache.logging.log4j.core.appender.RollingFileAppender for element RollingFile: java.lang.IllegalStateException: No factory method found for class org.apache.logging.log4j.core.appender.RollingFileAppender java.lang.IllegalStateException: No factory method found for class org.apache.logging.log4j.core.appender.RollingFileAppender
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.findFactoryMethod(PluginBuilder.java:229)
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.build(PluginBuilder.java:134)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createPluginObject(AbstractConfiguration.java:958)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:898)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:890)
at org.apache.logging.log4j.core.config.AbstractConfiguration.doConfigure(AbstractConfiguration.java:513)
at org.apache.logging.log4j.core.config.AbstractConfiguration.initialize(AbstractConfiguration.java:237)
at org.apache.logging.log4j.core.config.AbstractConfiguration.start(AbstractConfiguration.java:249)
at org.apache.logging.log4j.core.LoggerContext.setConfiguration(LoggerContext.java:545)
at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:261)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:166)
at org.elasticsearch.common.logging.LogConfigurator.configure(LogConfigurator.java:122)
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:307)
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132)
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:123)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:70)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84)
解决：
原来在执行yum -y install elasticsearch的时候，就已经自动创建了一个单独的管理用户elasticsearch，但是我又自己创建了一个elk用户，并且把data和log目录授权给elk，所以就会出现"Starting elasticsearch: 2018-06-12 15:13:50,287 main ERROR Unable to create file /var/log/elasticsearch/elk.log java.io.IOException: 权限不够"的报错。
因此只需要将/opt/elk/data和/var/log/elasticsearch目录权限改为elasticsearch:elasticsearch就好了：
然后重启服务成功：
[root@test101 init.d]# ./elasticsearch start
Starting elasticsearch: [ 确定 ]
[root@test101 init.d]# ps -ef|grep elasticsearch
elastic+ 5157 1 80 15:49 ? 00:00:08 /usr/local/jdk1.8.0_151/bin/java -Xms512m -Xmx512m -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+AlwaysPreTouch -server -Xss1m -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djna.nosys=true -Djdk.io.permissionsUseCanonicalPath=true -Dio.netty.noUnsafe=true -Dio.netty.noKeySetOptimization=true -Dio.netty.recycler.maxCapacityPerThread=0 -Dlog4j.shutdownHookEnabled=false -Dlog4j2.disable.jmx=true -Dlog4j.skipJansi=true -XX:+HeapDumpOnOutOfMemoryError -Des.path.home=/usr/share/elasticsearch -cp /usr/share/elasticsearch/lib/* org.elasticsearch.bootstrap.Elasticsearch -p /var/run/elasticsearch/elasticsearch.pid -d -Edefault.path.logs=/var/log/elasticsearch -Edefault.path.data=/var/lib/elasticsearch -Edefault.path.conf=/etc/elasticsearch
root 5177 921 0 15:50 pts/0 00:00:00 grep --color=auto elasticsearch
[root@test101 init.d]# netstat -tlunp|grep 9200
tcp6 0 0 :::9200 :::* LISTEN 5157/java
[root@test101 init.d]#
4、日志和数据目录权限异常，启动失败
在一次启动elasticsearch的时候启动失败，日志有提示"main ERROR Unable to create file /home/elk/logs/my-application_index_indexing_slowlog.log java.io.IOException: 权限不够"和"Caused by: java.nio.file.AccessDeniedException: /home/elk/data/nodes"。关键日志信息如下（下面两段日志是节选的，日志信息太多了，有很多重复的）：
[elk@docker bin]$ ./elasticsearch
2018-06-04 01:15:07,609 main ERROR Unable to create file /home/elk/logs/my-application.log java.io.IOException: 权限不够
at java.io.UnixFileSystem.createFileExclusively(Native Method)
at java.io.File.createNewFile(File.java:1012)
后面还有一段：
Caused by: java.lang.IllegalStateException: Failed to create node environment
at org.elasticsearch.node.Node.<init>(Node.java:268) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.node.Node.<init>(Node.java:245) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Bootstrap$5.<init>(Bootstrap.java:233) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:233) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:342) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132) ~[elasticsearch-5.6.0.jar:5.6.0]
... 6 more
Caused by: java.nio.file.AccessDeniedException: /home/elk/data/nodes
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84) ~[?:?]
日志报的"/home/elk/data/"和"/home/elk/logs/"目录都是在elasticsearch.yml配置文件里面配置的两个目录，查看权限果然不对，权限是elk的目录权限是elk，但是下面的data目录和logs目录权限还是root，因此引起了启动失败：
[root@docker home]# ll
drwx------ 5 elk elk 125 6月 3 17:35 elk #elk目录权限正常
[root@docker home]# cd elk/
[root@docker elk]# ll
总用量 0
drwxr-xr-x 2 root root 6 6月 3 17:34 data #下面的data和logs目录还是root
drwxr-xr-x 2 root root 6 6月 3 17:34 logs
解决：
将目录权限修改成elk之后，启动就OK了
[root@docker elk]# chown elk:elk -R ./*
[root@docker elk]# ll
总用量 0
drwxr-xr-x 2 elk elk 6 6月 3 17:34 data
drwxr-xr-x 2 elk elk 6 6月 3 17:34 logs
[root@docker elk]#
5、内存不够，启动失败
在一次使用虚拟机做实验的过程中启动elasticsearch遇到了这样的报错：
[elk@docker bin]$ ./elasticsearch
Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x0000000085330000, 2060255232, 0) failed; error='Cannot allocate memory' (errno=12)
#
# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 2060255232 bytes for committing reserved memory.
# An error report file with more information is saved as:
# /usr/local/elasticsearch-5.6.0/bin/hs_err_pid2819.log
解决：
原因：
查看了 /usr/local/elasticsearch-5.6.0/bin/hs_err_pid1027.log日志文件，出现这样的报错，有两种可能：
1、系统进程数达到上限了，部署服务的时候/etc/security/limits.conf文件修改没有生效。
2、确实物理内存不够
解决：
通过命令查看系统限制：ulimit -a查看open files不够大，如果不够大，就尝试通过设大该值：
[root@docker ~]# ulimit -n
1024
果然是部属的时候修改的/etc/security/limits.conf文件没有生效。于是将机器reboot了一下，在查看就生效了：
[root@docker ~]# ulimit -n
65536
但是在启动的时候还是报同样的错，查看了一下内存，这个虚拟机的内存只有1G，那应该就是物理内存不够了。目前还剩下这么多：
[root@docker ~]# free -h
total used free shared buff/cache available
Mem: 974M 119M 79M 7.7M 775M 680M
Swap: 819M 0B 819M
手动清理了一下内存：
[root@docker ~]# echo 3 > /proc/sys/vm/drop_caches
[root@docker ~]# free -h
total used free shared buff/cache available
Mem: 974M 114M 789M 7.7M 69M 739M
Swap: 819M 0B 819M
[root@docker ~]#
但是在启动报错依旧。
于是增加物理内存到2G：
[root@docker elk]# free -h
total used free shared buff/cache available
Mem: 1.8G 1.6G 77M 4K 72M 29M
Swap: 819M 691M 128M
然后切换到elk用户去启动服务，就OK了：
[elk@docker bin]$ ./elasticsearch #为了看启动日志就前台启动的，ctrl+c 进程就会over掉
检查端口，起来了
[root@docker elk]# netstat -tlunp|grep 9200
tcp6 0 0 10.0.0.16:9200 :::* LISTEN 9628/java
[root@docker elk]#
然后关掉进程重新后台启动：
[elk@docker bin]$ nohup ./elasticsearch >/dev/null 2>&1 & #后台启动
[2] 9808
[elk@docker bin]$ ps -ef|grep elasticsearch #检查进程
elk 9808 4115 10 01:29 pts/0 00:00:23 /usr/local/jdk1.8.0_151/bin/java -Xms2g -Xmx2g -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+AlwaysPreTouch -server -Xss1m -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djna.nosys=true -Djdk.io.permissionsUseCanonicalPath=true -Dio.netty.noUnsafe=true -Dio.netty.noKeySetOptimization=true -Dio.netty.recycler.maxCapacityPerThread=0 -Dlog4j.shutdownHookEnabled=false -Dlog4j2.disable.jmx=true -Dlog4j.skipJansi=true -XX:+HeapDumpOnOutOfMemoryError -Des.path.home=/usr/local/elasticsearch-5.6.0 -cp /usr/local/elasticsearch-5.6.0/lib/* org.elasticsearch.bootstrap.Elasticsearch
elk 9890 4115 0 01:32 pts/0 00:00:00 grep --color=auto elasticsearch
[elk@docker bin]$
[root@docker elk]# netstat -tlunp|grep 9200 #用root用户检查端口
tcp6 0 0 10.0.0.16:9200 :::* LISTEN 9808/java
[root@docker elk]#
6、 elasticsearch.yml的bind的IP写错，服务起不来
在一次安装 elasticsearc的时候，服务起不来，提示"Failed to bind to [9300-9400]"。启动服务报下面的错误：
[elk@host1 bin]$ ./elasticsearch
[2018-06-15T09:56:53,019][INFO ][o.e.n.Node ] [node1] initializing ...
[2018-06-15T09:56:53,141][INFO ][o.e.e.NodeEnvironment ] [node1] using [1] data paths, mounts [[/data (/dev/mapper/data-data)]], net usable_space [179.8gb], net total_space [179.9gb], spins? [possibly], types [xfs]
[2018-06-15T09:56:53,142][INFO ][o.e.e.NodeEnvironment ] [node1] heap size [1.9gb], compressed ordinary object pointers [true]
[2018-06-15T09:56:53,143][INFO ][o.e.n.Node ] [node1] node name [node1], node ID [F0PzQ9qSRPWq8YNcwjj0vg]
[2018-06-15T09:56:53,144][INFO ][o.e.n.Node ] [node1] version[5.6.0], pid[27627], build[781a835/2017-09-07T03:09:58.087Z], OS[Linux/3.10.0-514.el7.x86_64/amd64], JVM[Oracle Corporation/OpenJDK 64-Bit Server VM/1.8.0_102/25.102-b14]
[2018-06-15T09:56:53,144][INFO ][o.e.n.Node ] [node1] JVM arguments [-Xms2g, -Xmx2g, -XX:+UseConcMarkSweepGC, -XX:CMSInitiatingOccupancyFraction=75, -XX:+UseCMSInitiatingOccupancyOnly, -XX:+AlwaysPreTouch, -Xss1m, -Djava.awt.headless=true, -Dfile.encoding=UTF-8, -Djna.nosys=true, -Djdk.io.permissionsUseCanonicalPath=true, -Dio.netty.noUnsafe=true, -Dio.netty.noKeySetOptimization=true, -Dio.netty.recycler.maxCapacityPerThread=0, -Dlog4j.shutdownHookEnabled=false, -Dlog4j2.disable.jmx=true, -Dlog4j.skipJansi=true, -XX:+HeapDumpOnOutOfMemoryError, -Des.path.home=/usr/local/elasticsearch-5.6.0]
[2018-06-15T09:56:54,161][INFO ][o.e.p.PluginsService ] [node1] loaded module [aggs-matrix-stats]
[2018-06-15T09:56:54,162][INFO ][o.e.p.PluginsService ] [node1] loaded module [ingest-common]
[2018-06-15T09:56:54,162][INFO ][o.e.p.PluginsService ] [node1] loaded module [lang-expression]
[2018-06-15T09:56:54,162][INFO ][o.e.p.PluginsService ] [node1] loaded module [lang-groovy]
[2018-06-15T09:56:54,162][INFO ][o.e.p.PluginsService ] [node1] loaded module [lang-mustache]
[2018-06-15T09:56:54,162][INFO ][o.e.p.PluginsService ] [node1] loaded module [lang-painless]
[2018-06-15T09:56:54,163][INFO ][o.e.p.PluginsService ] [node1] loaded module [parent-join]
[2018-06-15T09:56:54,163][INFO ][o.e.p.PluginsService ] [node1] loaded module [percolator]
[2018-06-15T09:56:54,163][INFO ][o.e.p.PluginsService ] [node1] loaded module [reindex]
[2018-06-15T09:56:54,163][INFO ][o.e.p.PluginsService ] [node1] loaded module [transport-netty3]
[2018-06-15T09:56:54,163][INFO ][o.e.p.PluginsService ] [node1] loaded module [transport-netty4]
[2018-06-15T09:56:54,164][INFO ][o.e.p.PluginsService ] [node1] no plugins loaded
[2018-06-15T09:56:55,941][INFO ][o.e.d.DiscoveryModule ] [node1] using discovery type [zen]
[2018-06-15T09:56:56,770][INFO ][o.e.n.Node ] [node1] initialized
[2018-06-15T09:56:56,770][INFO ][o.e.n.Node ] [node1] starting ...
[2018-06-15T09:56:57,059][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [node1] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: BindTransportException[Failed to bind to [9300-9400]]; nested: BindException[Cannot assign requested address];
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:136) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:123) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:67) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84) ~[elasticsearch-5.6.0.jar:5.6.0]
Caused by: org.elasticsearch.transport.BindTransportException: Failed to bind to [9300-9400]
at org.elasticsearch.transport.TcpTransport.bindToPort(TcpTransport.java:771) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.transport.TcpTransport.bindServer(TcpTransport.java:736) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.transport.netty4.Netty4Transport.doStart(Netty4Transport.java:173) ~[?:?]
at org.elasticsearch.common.component.AbstractLifecycleComponent.start(AbstractLifecycleComponent.java:69) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.transport.TransportService.doStart(TransportService.java:209) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.common.component.AbstractLifecycleComponent.start(AbstractLifecycleComponent.java:69) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.node.Node.start(Node.java:694) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Bootstrap.start(Bootstrap.java:278) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:351) ~[elasticsearch-5.6.0.jar:5.6.0]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132) ~[elasticsearch-5.6.0.jar:5.6.0]
... 6 more
Caused by: java.net.BindException: Cannot assign requested address
at sun.nio.ch.Net.bind0(Native Method) ~[?:?]
at sun.nio.ch.Net.bind(Net.java:433) ~[?:?]
at sun.nio.ch.Net.bind(Net.java:425) ~[?:?]
at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223) ~[?:?]
at io.netty.channel.socket.nio.NioServerSocketChannel.doBind(NioServerSocketChannel.java:128) ~[?:?]
at io.netty.channel.AbstractChannel$AbstractUnsafe.bind(AbstractChannel.java:554) ~[?:?]
at io.netty.channel.DefaultChannelPipeline$HeadContext.bind(DefaultChannelPipeline.java:1258) ~[?:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeBind(AbstractChannelHandlerContext.java:501) ~[?:?]
at io.netty.channel.AbstractChannelHandlerContext.bind(AbstractChannelHandlerContext.java:486) ~[?:?]
at io.netty.channel.DefaultChannelPipeline.bind(DefaultChannelPipeline.java:980) ~[?:?]
at io.netty.channel.AbstractChannel.bind(AbstractChannel.java:250) ~[?:?]
at io.netty.bootstrap.AbstractBootstrap$2.run(AbstractBootstrap.java:365) ~[?:?]
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163) ~[?:?]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:403) ~[?:?]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:462) ~[?:?]
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858) ~[?:?]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_102]
[2018-06-15T09:56:57,822][INFO ][o.e.n.Node ] [node1] stopping ...
[2018-06-15T09:56:57,826][INFO ][o.e.n.Node ] [node1] stopped
[2018-06-15T09:56:57,826][INFO ][o.e.n.Node ] [node1] closing ...
[2018-06-15T09:56:57,839][INFO ][o.e.n.Node ] [node1] closed
[elk@host1 bin]$
[elk@host1 bin]$
[root@host1 bin]# netstat -tlunp|grep 9300
[root@host1 bin]# netstat -tlunp|grep 9200
[root@host1 bin]#
解决：
开始以为是端口被占用了，检查端口，发现并没有被占用：
[root@host1 bin]# netstat -tlunp|grep 9300
[root@host1 bin]# netstat -tlunp|grep 9200
[root@host1 bin]#
然后检查配置，发现 elasticsearch.yml文件里面有一行的IP写错了：
network.host: 10.0.0.10 #这一行的IP地址写错了，不是本机IP
修改elasticsearch.yml文件，将IP改正确，重新启动服务，就OK了
7、配置文件elasticsearch.yml的权限异常，导致启动失败
有一次在安装elasticsearch的时候，因为elasticsearch.yml文件改得有问题，就从原来备份的elasticsearch.yml.bak文件cp重新生成了一份elasticsearch.yml，改好之后启动报错不能加载配置文件：
[elk@es bin]$ ./elasticsearch
Exception in thread "main" 2018-09-14 09:04:49,470 main ERROR No log4j2 configuration file found. Using default configuration: logging only errors to the console. Set system property 'log4j2.debug' to show Log4j2 internal initialization logging.
SettingsException[Failed to load settings from /usr/local/elasticsearch-5.6.0/config/elasticsearch.yml]; nested: AccessDeniedException[/usr/local/elasticsearch-5.6.0/config/elasticsearch.yml];
at org.elasticsearch.node.InternalSettingsPreparer.prepareEnvironment(InternalSettingsPreparer.java:102)
at org.elasticsearch.cli.EnvironmentAwareCommand.createEnv(EnvironmentAwareCommand.java:72)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:67)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84)
Caused by: java.nio.file.AccessDeniedException: /usr/local/elasticsearch-5.6.0/config/elasticsearch.yml
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)
at sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:214)
at java.nio.file.Files.newByteChannel(Files.java:361)
at java.nio.file.Files.newByteChannel(Files.java:407)
at java.nio.file.spi.FileSystemProvider.newInputStream(FileSystemProvider.java:384)
at java.nio.file.Files.newInputStream(Files.java:152)
at org.elasticsearch.common.settings.Settings$Builder.loadFromPath(Settings.java:1032)
at org.elasticsearch.node.InternalSettingsPreparer.prepareEnvironment(InternalSettingsPreparer.java:100)
... 6 more
[elk@es bin]$
原来新生成的配置文件elasticsearch.yml还是root权限，用elk用户去启动，当然加载不了：
[root@es config]# ll
total 20
-rw-r----- 1 root root 2961 Sep 14 09:04 elasticsearch.yml
-rw-r----- 1 elk elk 2854 Sep 14 08:49 elasticsearch.yml.bak
-rw-rw---- 1 elk elk 3064 Sep 7 2017 jvm.options
-rw-rw---- 1 elk elk 4456 Sep 7 2017 log4j2.properties
[root@es config]#
解决：
修改配置文件elasticsearch.yml的权限，再重新启动就好了：
[root@es config]# chown elk:elk elasticsearch.yml
[root@es config]# ll
total 20
-rw-r----- 1 elk elk 2961 Sep 14 09:04 elasticsearch.yml
-rw-r----- 1 elk elk 2854 Sep 14 08:49 elasticsearch.yml.bak
-rw-rw---- 1 elk elk 3064 Sep 7 2017 jvm.options
-rw-rw---- 1 elk elk 4456 Sep 7 2017 log4j2.properties
[root@es config]#
8、yum安装的elasticsearch，找不到java路径，启动失败
今天使用yum安装elasticsearch的过程中，发现elasticsearch起不来，messages日志有如下的报错：
May 31 14:00:19 test103 systemd: Started Elasticsearch.
May 31 14:00:19 test103 systemd: Starting Elasticsearch...
May 31 14:00:19 test103 elasticsearch: which: no java in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin) #elasticsearch在这个路径下面去找java，没有找到
May 31 14:00:19 test103 systemd: elasticsearch.service: main process exited, code=exited, status=1/FAILURE
May 31 14:00:19 test103 elasticsearch: warning: Falling back to java on path. This behavior is deprecated. Specify JAVA_HOME
May 31 14:00:19 test103 elasticsearch: could not find java; set JAVA_HOME
May 31 14:00:19 test103 systemd: Unit elasticsearch.service entered failed state.
May 31 14:00:19 test103 systemd: elasticsearch.service failed.
报错说找不到java，但是实际上我是安装过jdk了，查看当前java路径为：
[root@test103 ~]# whereis java
java: /usr/local/jdk1.8.0_151/bin/java
[root@test103 ~]#
然后查看/usr/local/sbin/目录下没有java，所以elasticsearch在启动的时候找不到java路径。
解决：
把/usr/local/jdk1.8.0_151/bin/java做了个软连接到 /usr/local/sbin下面：
[root@test103 sbin]# ln -s /usr/local/jdk1.8.0_151/bin/java /usr/local/sbin/java
[root@test103 sbin]# ll
总用量 0
lrwxrwxrwx 1 root root 32 5月 31 14:01 java -> /usr/local/jdk1.8.0_151/bin/java
现在查看java路径，就有/usr/local/sbin/java了：
[root@test103 sbin]# whereis java
java: /usr/local/sbin/java /usr/local/jdk1.8.0_151/bin/java
[root@test103 sbin]#
然后重新启动elasticsearch，发现就可以正常启动了：
[root@test103 sbin]# systemctl start elasticsearch
[root@test103 sbin]# ps -ef|grep elasticsearch
elastic+ 13635 1 70 14:02 ? 00:00:12 /usr/local/sbin/java -Xms1g -Xmx1g -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -Des.networkaddress.cache.ttl=60 -Des.networkaddress.cache.negative.ttl=10 -XX:+AlwaysPreTouch -Xss1m -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djna.nosys=true -XX:-OmitStackTraceInFastThrow -Dio.netty.noUnsafe=true -Dio.netty.noKeySetOptimization=true -Dio.netty.recycler.maxCapacityPerThread=0 -Dlog4j.shutdownHookEnabled=false -Dlog4j2.disable.jmx=true -Djava.io.tmpdir=/tmp/elasticsearch-7859403592413850651 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/var/lib/elasticsearch -XX:ErrorFile=/var/log/elasticsearch/hs_err_pid%p.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintTenuringDistribution -XX:+PrintGCApplicationStoppedTime -Xloggc:/var/log/elasticsearch/gc.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=32 -XX:GCLogFileSize=64m -Des.path.home=/usr/share/elasticsearch -Des.path.conf=/etc/elasticsearch -Des.distribution.flavor=default -Des.distribution.type=rpm -cp /usr/share/elasticsearch/lib/* org.elasticsearch.bootstrap.Elasticsearch -p /var/run/elasticsearch/elasticsearch.pid --quiet
elastic+ 13692 13635 0 14:02 ? 00:00:00 /usr/share/elasticsearch/modules/x-pack-ml/platform/linux-x86_64/bin/controller
root 13698 10140 0 14:02 pts/0 00:00:00 grep --color=auto elasticsearch
[root@test103 sbin]# netstat -tlunp|grep 9300
tcp6 0 0 10.0.0.103:9300 :::* LISTEN 13635/java
[root@test103 sbin]# netstat -tlunp|grep 9200
tcp6 0 0 10.0.0.103:9200 :::* LISTEN 13635/java
[root@test103 sbin]#