在Windows里用VBoxManage将动态扩展硬盘的vhd转成固定大小的

问题：从镜像站下载的FreeBSD虚拟硬盘文件vhd是动态扩展的，虽然可以在VitualBox里使用，但无法在Linux系统里使用dd命令还原。


尝试：


1.下载FreeBSD的镜像文件，如国内的可从阿里云镜像点下载 https://mirrors.aliyun.com/freebsd/releases/VM-IMAGES/12.0-RELEASE/amd64/Latest/FreeBSD-12.0-RELEASE-amd64.vhd.xz


2.下载到本地后，用7-zip解压，得到 FreeBSD-12.0-RELEASE-amd64.vhd 文件


3.使用VBoxManage.exe程序，将vhd磁盘文件从动态扩展的转成固定大小的类型，如 VBoxManage.exe clonemedium disk "I:\vhd\FreeBSD-12.0-RELEASE-amd64.vhd3\FreeBSD-12.0-RELEASE-amd64.vhd" "I:\vhd\FreeBSD-12.0-RELEASE-amd64.vhd3\FreeBSD-12.0-RELEASE-amd64-b.vhd" –variant Fixed









4.如提示原vhd磁盘的uuid重复，可先生成新的uuid，如 VBoxManage.exe internalcommands sethduuid "I:\vhd\FreeBSD-12.0-RELEASE-amd64.vhd3\FreeBSD-12.0-RELEASE-amd64.vhd"




5.通过dd命令，成功将固定大小类型的vhd文件复制到指定的硬盘上


参考：
* https://www.howtogeek.com/312456/how-to-convert-between-fixed-and-dynamic-disks-in-virtualbox/
* https://knowledge.zomers.eu/virtualbox/Pages/Changing-the-UUID-of-a-virtual-disk.aspx