vagrant up 时如何指定不同的磁盘？

Question

在Windows上用Vagrant,vagrantup后安装路径自动找了我的L盘，怎么给它设置成别的盘？
Progressstate:VBOX_E_FILE_ERROR
VBoxManage.exe:error:Applianceimportfailed
VBoxManage.exe:error:Couldnotcreatetheclonemedium'L:\VirtualBoxVMs\ubun
tu-cloudimg-trusty-vagrant-amd64\box-disk1.vmdk'.
VBoxManage.exe:error:VMDK:couldnotcreatenewgraindirectoryin'L:\Virtual
BoxVMs\ubuntu-cloudimg-trusty-vagrant-amd64/box-disk1.vmdk'(VERR_DISK_FULL).
VBoxManage.exe:error:VMDK:errorwritingdescriptorin'L:\VirtualBoxVMs\ubun
tu-cloudimg-trusty-vagrant-amd64\box-disk1.vmdk'(VERR_DISK_FULL)
VBoxManage.exe:error:Details:codeVBOX_E_FILE_ERROR(0x80bb0004),componentA
ppliance,interfaceIAppliance
VBoxManage.exe:error:Context:"int__cdeclhandleImportAppliance(structHandle
rArg*)"atline779offileVBoxManageAppliance.cpp