linux scp命令 nohup后台运行
跨服务器拷贝大文件，传输时间很长，若ssh终端关闭，传输会停止，可用如下方法设置nohup后台运行,实测有效
https://www.cnblogs.com/jyzhao/p/6253728.html
nohup的概念
The purview of science grows rapidly with time. It is the responsibility of each generation to join new insights to old wisdom, and to distill the key ideas for the next generation --James P. Sethna
