A, root users to run error
Exception in thread "main" java.lang.RuntimeException: don't run elasticsearch as root.
Solution:
#添加es用户
useradd es
#给es用户授权目录权限
chown es:es -R /usr/es/
# 切换到es用户运行接口
su es
# 执行即可
./elasticsearch -d
Second, the file number of threads operational error
ERROR: [2] bootstrap checks failed
[1]: max file descriptors [4096] for elasticsearch process is too low, increase to at least [65536]
Solution
Switch to root, edit limits.conf configuration file and add the following similar
# 切换到root用户
su root
vi /etc/security/limits.conf
* soft nofile 65536
* hard nofile 131072
* soft nproc 2048
* hard nproc 4096
#备注：* 代表Linux所有用户名称（比如 hadoop）
#保存、退出、重新登录才可生效
Third, the maximum virtual memory error
The reason: the maximum virtual memory is too small
ERROR: [1] bootstrap checks failed
[1]: max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
Solution
The switch to root, modify the configuration file sysctl.conf
vi /etc/sysctl.conf
#添加下面配置：
vm.max_map_count=655360
#并执行命令
sysctl -p
#然后重新启动elasticsearch，即可启动成功
