Re: [Libvir] default hypervisor selection

On Thu, 2008-02-21 at 14:57 +0000, Daniel P. Berrange wrote: (Re-suggesting something that was shot down before just in case it makes more sense to people this time around :-) I've never liked the fact that the individual drivers are exposed in the API and to the user. IMHO, the default behaviour for open(NULL), virsh, virt-manager etc. should be to talk to *all* drivers and aggregate the results. When you define a VM, that's the only time you should care about Xen vs. KVM etc. After that, it should just be a question of referring to a VM by name. The only time you should really need to specify a URI is when connecting to a remote host, IMHO. Adding a heuristic to select sensible driver by default won't help someone running e.g. KVM VMs and linux containers on the same host, which I don't think is such a crazy notion. Yes, you'd be trying to merge overlapping namespaces, but some ideas on that front: - If you simply prevent someone defining a VM using the same name as an existing VM defined via another driver, that gets you 90% there - Never aggregate a user's private namespace with the system namespace - e.g. for a normal user, an open(NULL) connection would only show the user's own VMs and we'd have another URI (or e.g. a virsh --system switch) for dealing with system-level VMs - If someone connects directly to a driver, or goes behind libvirt's back, and creates a VM with conflicting names, then just return an error if someone tries to perform an operation using the conflicting name ... and force the user to again connect to the specific driver or go behind libvirt's back - Also, figure out some way to deprecate the VM "id" attribute which is the most obvious point of conflict ... name and uuid should be enough identifiers, surely Cheers, Mark.