systemctl start foo.service:启动服务
systemctl restart foo.service:重启服务
systemctl stop foo.service:停止服务
systemctl reload foo.service:重新加载配置文件(不终止服务)
systemctl status foo.service:查看服务状态
systemctl enable foo.service:开机自动启动
systemctl disable foo.service:开机不自动启动
systemctl is-enabled foo.service:查看特定服务是否为开机自动启动
systemctrl list-unit-files —type=service:查看各个级别下服务的启动与禁用情况
