I wrote a small patch (intro, patch) which adds a Secure Shell (ssh) block device to qemu. With this patch you could access a remote disk image or device by doing:
qemu -drive file=ssh://host/path/to/file,if=virtio,cache=none
QEMU ssh’es into “host” and opens /path/to/file. For the initial version of this patch you will need to set up ssh-agent access to the remote server.
The motivation behind this patch is to allow libguestfs to access remote disks using ssh the same way we already do with NBD. Secure Shell is ubiquitous, so for the majority of users libguestfs-over-qemu/ssh would let them use disks remotely with zero configuration.

Rich, this is brilliant. Keep the good stuff coming.
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