1，could not find java in JAVA_HOME or bundled at /usr/local/java/jdk1.8.0_181/bin/java
解决：在安装jdk8后配置环境变量时JAVA_HOME：/usr/local/java/jdk1.8.0_231路径结尾未加/
2，ElasticsearchUncaughtExceptionHandler] … can not run elasticsearch as root
解决：根据报错详情日志看出是elasticsearch.yml配置文件中修改network.host:47.97.26.218时冒号后未加空格
3、BindTransportException[Failed to bind to [9300-9400]
解决：配置文件elasticsearch.yml 将 network.host: 47.97.26.218 修改为本机IP 0.0.0.0
4、unable to install syscall filter:
解决：在配置文件elasticsearch.yml最后一行添加bootstrap.system_call_filter: false
5、java.nio.file.AccessDeniedException: …/elasticsearch-7.4.0/config/jvm.options
解决：给es用户赋予elasticsearch-7.0.0下所有文件的权限 chown -R es:es /usr/local/elasticsearch-7.0.0/
6、max number of threads [1024] for user [lishang] likely too low
解决：切换root用户，修改limits.d目录下的配置文件vim /etc/security/limits.d/90-nproc.conf
7、max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
解决：切到root用户执行sysctl -w vm.max_map_count=262144，在 /etc/sysctl.conf文件最后添加一行vm.max_map_count=262144
