一、root无法启动
1、增加账户
groupadd elsearchuseradd elsearch -g elsearch -p elasticsearch

2、修改文件权限
chown -R elsearch:elsearch elasticsearch.xx.xx

二、修改机器的最大描述符
max file descriptors [65535] for elasticsearch process is too low, increase to at least [65536]
maxfile descriptors为最大文件描述符，设置其大于65536即可
修改/etc/security/limits.conf

三、修改map数量
max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
vim /etc/sysctl.conf
vm.max_map_count=262144
sysctl -p