I think I have already sent an email about this to the list, but no reply on this specific point. Libvirt is currently capable of storing storage, networks, the only thing that is really missing is the direct storage of domains. I wonder if a patch would be accepted that stores defined domains (live) to disk upon change. Some sort of dumpxml per define/attach/etc. when a domain is undefined the file is removed.

DP: Would a patch be accepted that makes this configurable for *all* implementations? So that by after configuration a file is saved, and is queried after the platform specific implementation doesn't list the domain as defined? List Defined domains: - Query current implementation - If defined merge all non available domains. In principle what I want to see is that if a domain is not defined in the specific hypervisor, the domain file can be queried. I know I can implement this behavior in my own code, but I really thing this would be a cool thing for more people.

Daniel P. Berrange schreef: >On Wed, Jul 23, 2008 at 11:54:11AM +0200, Stefan de Konink wrote: >>DP: Would a patch be accepted that makes this configurable for *all* >>implementations? So that by after configuration a file is saved, and is >>queried after the platform specific implementation doesn't list the >>domain as defined? >> >>List Defined domains: >> - Query current implementation >> - If defined merge all non available domains. >> >>In principle what I want to see is that if a domain is not defined in >>the specific hypervisor, the domain file can be queried. I know I can >>implement this behavior in my own code, but I really thing this would be >>a cool thing for more people. > >This doesn't make any sense. We have APIs for listing & defining inactive >domains. The individual drivers implement these APIs according to the >required API contract, and the underlying impl is not something which any >application using libvirt need know or care about. If your application is >relying on the inactive domains being stored in files it is broken. Or you could say that libvirt is broken because it isn't able to distribute the inactive domains across the network in a consistent way.

Daniel P. Berrange schreef: >On Wed, Jul 23, 2008 at 12:43:25PM +0200, Stefan de Konink wrote: >>Daniel P. Berrange schreef: >>>On Wed, Jul 23, 2008 at 11:54:11AM +0200, Stefan de Konink wrote: >>>>DP: Would a patch be accepted that makes this configurable for *all* >>>>implementations? So that by after configuration a file is saved, and is >>>>queried after the platform specific implementation doesn't list the >>>>domain as defined? >>>> >>>>List Defined domains: >>>>- Query current implementation >>>>- If defined merge all non available domains. >>>> >>>>In principle what I want to see is that if a domain is not defined in >>>>the specific hypervisor, the domain file can be queried. I know I can >>>>implement this behavior in my own code, but I really thing this would >>>>be a cool thing for more people. >>>This doesn't make any sense. We have APIs for listing & defining >>>inactive domains. The individual drivers implement these APIs according >>>to the >>>required API contract, and the underlying impl is not something which any >>>application using libvirt need know or care about. If your application is >>>relying on the inactive domains being stored in files it is broken. >>Or you could say that libvirt is broken because it isn't able to >>distribute the inactive domains across the network in a consistent way. > >No, because that is not libvirt's job. The goal of libvirt is to provide >an API for managing virtualization capabilities on a host. Data center or >network management is an application level problem, out of scope for >libvirt. That calls for a libvirt-fork that does implement what is needed to consistently providing a replicated pool of domains; call it libvirt-datacenter-edition. I think it is the biggest non sense for implementing shortcommings/management in kvm/qemu, but don't provide these to the other hypervisors 'just because they implement it theirselves locally'. It is non-trivial to provide a 'xenstored' for the complete network, while it is relatively easy to put an NFS dir on the libvirt xml configs.