On 07/28/2010 01:24 PM, Daniel P. Berrange wrote:

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We explicitly don't support external driver plugins in libvirt for a couple of reasons

- We don't want to support use of closed source plugins - We don't want to guarentee stability of any aspect of libvirt's internal API

We would like to see support for the various vendor specific iSCSI extensions to allow volume creation/deletion, but want that code to be part of the libvirt codebase.

The APIs can also invoke standard snmpget/set methods to talk to the target. All standard distributions ship with a net-snmp implementation. Would an implementation of the APIs that invokes snmpset/gets be an amenable solution?

Namespace clash ! The virDomainSnapshot APIs are per-hypervisor. They do snapshotting of the guest VM (including its storage).

I was actually just talking about the storage backends though which can do snapshots independently of any hypervisor. See the<backingstorage> element here:

http://libvirt.org/formatstorage.html#StorageVolBacking

This is already implemented with the LVM pool doing LVM snapshots. We also use it for external qcow2 backing files.

There are certain benefits of allowing snapshots/backup to happen in the storage and thereby save CPU cycles. It becomes even more visible with large TB storage where in a simple qcow2 backup copy could take a long time.