I finally have some time to investigate Eric's suggestion [1] to add virDomainMigrateGetMaxSpeed API and track current value in domainXML. WRT the XML representation, it seems this best fits under the existing lifecycle controls, e.g. a new "on_migrate" element. I'm not sure if this should be kept simple and rather flat such as <on_migrate max-speed='1000000000' /> or a little more expressive and extensible with something like <on_migrate> <bandwidth peak='1000000000' /> </on_migrate> Any comments on these representations or perhaps alternative suggestions? Regards, Jim [1] https://www.redhat.com/archives/libvir-list/2011-August/msg00224.html