安装rngd服务（熵服务）

yum install rng-tools

启动服务

systemctl start rngd

查看熵池

watch -n 1 cat /proc/sys/kernel/random/entropy_avail

启动错误

chip@chip:/var/lib/tomcat8/logs$ systemctl status rng-tools.service
● rng-tools.service - (null)
   Loaded: loaded (/etc/init.d/rng-tools)
   Active: failed (Result: exit-code) since Fri 2020-08-28 09:25:31 UTC; 1min 2s ago
  Process: 25318 ExecStart=/etc/init.d/rng-tools start (code=exited, status=1/FAILURE)

手动启动报错

chip@chip:/var/lib/tomcat8/logs$ /etc/init.d/rng-tools start
Starting Hardware RNG entropy gatherer daemon: (Hardware RNG device inode not found)
/etc/init.d/rng-tools: Cannot find a hardware RNG device to use.
原因:熵源配置错误

修改熵源配置

sudo sed -i -r '/^HRNGDEVICE/d;/#HRNGDEVICE=\/dev\/null/a HRNGDEVICE=/dev/urandom' /etc/default/rng-tools

重新启动OK