lsof, fuser 命令杀进程。target is busy (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1).)
http://www.cnblogs.com/peida/archive/2013/02/26/2932972.html
https://blog.csdn.net/lengyue1084/article/details/51477872
https://blog.csdn.net/ygtlovezf/article/details/78718147
my solution:
1. chcek the node under /dev
2. sudo mount an avialable node
for example, $ sudo mount /dev/sde /storage_3