On Mon, May 02, 2011 at 05:31:00PM -0600, Eric Blake wrote:
> Consider the case of a guest that has multiple virtual disks, some
> residing on shared storage (such as the OS proper) and some on local
> storage (scratch space, where the OS has faster response if the virtual
> disk does not have to go over the network, and possibly one where the
> guest can still work even if the disk is hot-unplugged). During
> migration, you'd want different handling of the two disks (the
> destination can already see the shared disk, but must either copy the
> contents or recreate a blank scratch volume for the local disk).
>
> Or, consider the case where a guest has one disk as qcow2 (it is not
> modified frequently, and benefits from sharing a common backing file
> with other guests), while another disk is raw (for better read-write
> performance). Right now, 'virsh snapshot' fails, because it only works
> if all disks are qcow2; and in fact it may be the case that it is
> desirable to only take a snapshot of a subset of the domain's disks.
There's a problem here, but I don't much like the solution. It's
going to be very clumsy to extend (say) "virsh migrate" or
virt-manager to support this.
How about just adding flags into the disk XML, eg:
<disk>
...
<flags>
<migrate>false</migrate>
<snapshot>false</snapshot>
</flags>
</disk>
(Don't sweat the details; the important point is that these are a
property of the disk which is permanently attached to that disk
through the XML).
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming blog: http://rwmj.wordpress.com
Fedora now supports 80 OCaml packages (the OPEN alternative to F#)
http://cocan.org/getting_started_with_ocaml_on_red_hat_and_fedora
--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list