但还是遇到了连接不稳定，很容易掉连接的问题。
查看/var/log/samba/目录下的log文件，发现出现了panic的错误，解决办法如下：
Samba on Ubuntu problem smb_panic()
Try to use Samba on Ubuntu in the VirtulBox, access from Windows always failed,
Check the Samba log:
tail /var/log/samba/log.lenovo-xhl-pc
Result as below (partially copy),
../source3/lib/util.c:801(smb_panic_s3) smb_panic(): calling panic action
This command resolved the problem,
$ apt-get install --reinstall libsmbclient libsmbclient-dev libtevent0 libtalloc2
It seems that the new samba package poorly specified the dependencies it needed, so require to re-install these library.
Reference link:
https://answers.launchpad.net/ubuntu/+question/291448