如何清理虚拟机缓存文件

1. 首先需要在真机安装 virt-sysprep命令

yum whatprovides */virt-sysprep
yum install libguestfs-tools -y

2. 清理虚拟机临时及缓存文件命令：

virt-sysprep -d 虚拟机名

3. 有时它会报错，信息如下：

[   0.0] Examining the guest ...
virt-sysprep: error: libguestfs error: could not create appliance through 
libvirt.

Try running qemu directly without libvirt using this environment variable:
export LIBGUESTFS_BACKEND=direct

Original error from libvirt: \u4e0d\u652f\u6301\u7684\u914d\u7f6e\uff1ashared access for disk 
'sdb' requires use of supported storage format [code=67 int1=-1]

If reporting bugs, run virt-sysprep with debugging enabled and include the 
complete output:

  virt-sysprep -v -x [...]

解决：执行下面命令更新包即可

yum upgrade libguestfs-tools
virt-sysprep -d 虚拟机名