creating the Amazon EC2 EIP vm, in the first time creation was fail, but second time passed

[lstfyt]

creating the Amazon EC2 EIP vm, in the first time creation was fail, but second time passed.
UI log as following:

{"org.zstack.header.vm.APICreateVmInstanceMsg":{"name":"vm-5u98","description":null,"instanceOfferingUuid":"7192c1de6e3945dfbdf6ed693d8f9b07","imageUuid":"cc65d5cfbcf042ca97abcb93f08b9728","l3NetworkUuids":["4fc3ac24dda846968588638cd6ccaed8"],"rootDiskOfferingUuid":null,"dataDiskOfferingUuids":[],"zoneUuid":"0e2d2e5e39df4b23ab3354e1943b557f","clusterUuid":"39c65a4e4f974451bdfc0ef3e97cbb5c","hostUuid":"c78daf36bf5c41b59dedb68499ee4421","resourceUuid":"3d1a985c0510438786d3b2a0b94608e8","defaultL3NetworkUuid":"4fc3ac24dda846968588638cd6ccaed8","systemTags":[],"session":{"uuid":"3414ce8cef704da883a6d730350b7530"}}} {"org.zstack.header.vm.APICreateVmInstanceEvent":{"success":false,"apiId":"b4775f46452d45d8bd521a3a103270a1","headers":{"schema":{}},"error":{"code":"SYS.1006","cause":{"code":"HOST.1005","description":"Failed to start vm on hypervisor","details":"failed to start vm[uuid:d414d0292f14453a972428a67355ccc6 name:virtualRouter.l3.4fc3ac24dda846968588638cd6ccaed8] on kvm host[uuid:c78daf36bf5c41b59dedb68499ee4421, ip:192.168.200.199], because unable to start vm[uuid:d414d0292f14453a972428a67355ccc6, name:virtualRouter.l3.4fc3ac24dda846968588638cd6ccaed8], libvirt error: Unable to create tap device vnic2.0: Device or resource busy"},"description":"An operation failed","details":"failed to start vm[uuid:d414d0292f14453a972428a67355ccc6 name:virtualRouter.l3.4fc3ac24dda846968588638cd6ccaed8] on kvm host[uuid:c78daf36bf5c41b59dedb68499ee4421, ip:192.168.200.199], because unable to start vm[uuid:d414d0292f14453a972428a67355ccc6, name:virtualRouter.l3.4fc3ac24dda846968588638cd6ccaed8], libvirt error: Unable to create tap device vnic2.0: Device or resource busy"},"id":"ec61edbe5d7b44d9bbf6ceaaa9d36c1a","creatingTime":1453646052256}}