nfs錯誤:mount: wrong fs type, bad option, bad superblock

root@leon-VirtualBox:/home/leon# mount -t nfs 127.0.0.1:/home/leon/nfs /mnt
mount: wrong fs type, bad option, bad superblock on 127.0.0.1:/home/leon/nfs,
       missing codepage or helper program, or other error
       (for several filesystems (e.g. nfs, cifs) you might
       need a /sbin/mount.<type> helper program)
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

解決方法：

apt-get install nfs-common