elasticsearch 启动失败，查看日志报错：

[1] bootstrap checks failed
[1]: max number of threads [1024] for user [elasticsearch] is too low, increase to at least [4096]

打开 /etc/security/limits.d/90-nproc.conf 注释掉* soft nproc 1024 或者调大

# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.

#*          soft    nproc     1024
root       soft    nproc     unlimited