Il 19/03/2014 18:46, Dr. David Alan Gilbert ha scritto:
* Serge E. Hallyn (se...@hallyn.com) wrote:
Quoting Dr. David Alan Gilbert (dgilb...@redhat.com):
* Serge E. Hallyn (se...@hallyn.com) wrote:
Although, some people are using newer qemu with '-M pc-1.0'. So we'd be
stopping thing from migrating to support the people coming from qemu-kvm.
Hmm.
What sometimes happens is that you create a VM (lets say with virt-manager)
on an old installation, and it has the XML file for that VM which I think
includes the machine type. You upgrade your host or copy your VMs over
and so you still use the old machine definition, and hence still have the
-M pc-1.0
Right, but so long as it is a shutdown vm image, it shouldn't matter to
this case whether qemu 1.7 uses the old qemu-kvm cirrus vga ram size, or
the qemu ram size, right?
Right - but they might have kept it as -M pc-1.0 on purpose, so that they
can migrate it back to another machine with an older qemu.
No, this is not supported upstream. Upstream only supports forward
migration.
Some people have snapshots rather than just disk images taken with particular
versions and they expect those to be reloadable into newer versions.
Disk snapshots should be fine right? Live snapshots no, but then
I didn't they were actually very well supported anyway. In any case,
they point would remain that if x% of people have snapshots from qemu-kvm,
and the rest have snapshots created using qemu but older machine types,
then whether or not we change the values, either way the other x% or
100-x % will not be able to restore...
This is correct.
Paolo
