vagrant故障記--升級虛擬機linux內核致使沒法掛載共享文件夾

i'm new to use vagrant，今天升級了下vbox裏的ubuntu12.04內核，結果vagrant reload後出現報錯。

Failed to mount folders in Linux guest. This is usually because

the "vboxsf" file system is not available. Please verify that

the guest additions are properly installed in the guest and

can work properly. The command attempted was:

mount -t vboxsf -o uid=id -u vagrant,gid=getent group vagrant | cut -d: -f3 vagrant /vagrant

mount -t vboxsf -o uid=id -u vagrant,gid=id -g vagrant vagrant /vagrant

The error output from the last command was:

stdin: is not a tty

/sbin/mount.vboxsf: mounting failed with the error: No such device

vagrant ssh登錄後發現共享文件夾沒了，無奈Google之，以後找到兩種方法。

1,sudo /etc/init.d/vboxadd setup

2,sudo apt-get install virtualbox-guest-utils

vagrant reload後問題完美解決。