参考：https://www.cnblogs.com/travis-li/p/12550370.html

cd /etc/ssh/
# 修改配置
vim sshd_config

# 开启服务
sudo service sshd start# 检查
ps -e | grep sshd

# 开机自启
systemctl enable sshd.service# 查看(验证)开机自启服务
[root@localhost liangshijie]# systemctl list-unit-files | grep sshd
sshd-keygen.service                           static
sshd.service                                  enabled
sshd@.service                                 static
sshd.socket                                   disabled