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