在 2012-09-11二的 18:00 +0100，Daniel P. Berrange写道： > > > > Good point - the new flag is necessary, and must be user-visible. At > > which point, do we argue that use of the MIGRATE_OFFLINE flag > > automatically implies MIGRATE_PERSISTENT, or should it be an error > > unless the user explicitly requests both flags? > > It sort of depends what you consider the semantics of MIGRATE_OFFLINE to > be. You can consider it to be a flag indicating that the guest must be > in the shutoff state curently, or you can consider it to be a > permission flag to indicate that migration is allowed if the guest > is offline. The difference here is subtle - basically comes down > to whether you raise an error if OFFLINE is set, and the guest is > currently running. > > In the case where you consider it a permission flag (which is what is > currently implemented), then we must mandate use of the PERSISTENT > flag, otherwise you get wierd semantics. eg The persistent config would > not be copied if running, but would be copied if shutoff. > > If you consider it a state flag, then I don't think it matters so much, > though I would still prefer to see the MIGRATE_PERSISTENT flag specified > explicitly. It would let you deal with a case where you have a shutoff > guest, and you migrate the storage (using the appropriate flag) but do > not migrate the config. > Yes, implicit flags really lead to misunderstanding. > Daniel -- liguang lig.fnst@xxxxxxxxxxxxxx FNST linux kernel team -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list