If inscribe
Don't know whether I centos7 a bug or is it a small update
Early centos7 before all, if not umount, prompt the disk busy,
However on centos7 don't need umount, mount can be mounted directly to the new path, but also in the original file of the path
But, there is a small problem, a new path and the original path, there will be the original path of files,
Have bosses know this thing ~