Re: [Qemu-devel] -loadvm and disk only snapshot

[Vasiliy Tolstov]

2015-12-16 19:19 GMT+03:00 Eric Blake <address@hidden>:
> Won't work (qemu is not able to load disk snapshots without memory).
> What libvirt does instead is to use qemu-img snapshot -c to change the
> snapshot back to the active layer, then boot qemu fresh on the correct
> contents.
>

qemu-img snapshot -a ? as i see -c creates new snapshot.

> Of course, patches to change behavior aren't out of the question, but
> there's already a lot of cruft there to be aware of, and making sure we
> don't regress libvirt behavior.

My needed use case - create multilayered qcow2 image. Base layer -
clean fresh (for example debian) system, next layer - LAMP, next layer
RAILS (base on top of clean debian system) and so on.
I want to create images from packer and want to write packer plugin
for this case (installer that able to read from qcow2 file i create
later).

Does it possible with qemu-img snapshots with my use case? I don't
want to snapshot memory because i don't need it. To get consistent
snapshots i can sync disk or freeze fs by ioctl.




-- 
Vasiliy Tolstov,
e-mail: address@hidden