ES启动报错 ：could not fidn java; set JAVA_HOME or ensure java is in PATH

环境 ： Ubuntu 16.04
ES人软件包 ： tar.gz

1、报错信息 ：could not fidn java; set JAVA_HOME or ensure java is in PATH

解决办法 ： 制作软连接
解决办法 ：制作软连接
ln -s /usr/local/jdk1.8.0_XXX/bin/java /usr/bin/java

2、制作软连接之后，又有一个报错

报错信息 ：

main ERROR RollingFileManager (/usr/local/elasticsearch-6.2.3/logs/elasticsearch.log)
main ERROR Could not create plugin of type class org.apache.logging.log4j.core.appender
main ERROR Unable to invoke factory method in class org.apache.logging

main ERROR Null object returned for RollingFile in Appenders.
main ERROR Unable to locate appender "rolling" for logger config "root"

解决办法 ：
elasticsearch.log (Permission denied)
1、main ERROR RollingFileManager (/usr/local/elasticsearch-6.0.0/logs/elasticsearch.log) java.io.FileNotFoundException: /usr/local/elasticsearch-6.0.0/logs/elasticsearch.log (Permission denied) java.io.FileNotFoundException: /usr/local/elasticsearch-6.0.0/logs/elasticsearch.log (Permission denied)
解决办法 ：
将es安装目录及其子目录赋予权限：

sudo chown -R 用户 elasticsearch-6.0.0

sudo chgrp -R 用户组 elasticsearch-6.0.0

重启ES,查看报错信息:



另一个报错，虚拟内存不足：

ERROR: [1] bootstrap checks failed
[1]: max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]

解决办法
修改/etc/security/limits.conf，修改到提示值即可

# vim /etc/security/limits.conf
* hard nofile 65536

修改/etc/sysctl.conf

 vim /etc/sysctl.conf 
添加配置：vm.max_map_count=262144，然后执行命令

保存配置：

#sysctl -p

重启es

elasticsearch@ubuntu:/usr/local/elasticsearch-6.2.3$ ./bin/elasticsearch

运行结果

查看端口以及进程

扩展

1、当设置完毕的时候还是出现如下报错"logstash: could not find java; set JAVA_HOME or ensure java is in PATH"
这是因为缺少个java的软连接，做个软连接即可解决此问题

环境变量
# echo $PATH
/usr/local/jdk/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin

查看整个系统的变量，
# set |grep JAVA_HOME

#vim ~/.bash_profile

PATH=$PATH:$HOME/bin
export JAVA_HOME=/usr/local/jdk
export PATH=$PATH:/usr/local/jdk/bin

生效
# source  ~/.bash_profile
查看变量值
# set |grep JAVA_HOME
JAVA_HOME=/usr/local/jdk

制作软连接

# ln -s /usr/local/jdk/bin/java   /usr/bin/java
#systemctl restart logstas
# systemctl status logstash

参考链接 ：

https://blog.csdn.net/u010781176/article/details/79489151
https://blog.csdn.net/weixin_34239169/article/details/88040592

could not find java;set JAVA_HOME or ensure java报错 ： https://blog.csdn.net/qq_34930488/article/details/102629121