错误日志：
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [req-56f28be4-e8cf-43f1-b6ac-72e3e2baea39 0eae95173a72433997b9c950431367fa 049c7b2ff4774362b591fe89dd5eb8f3 - default default] [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] Instance failed to spawn: VirtualInterfaceCreateException: Virtual Interface creation failed
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] Traceback (most recent call last):
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 2251, in _build_resources
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] yield resources
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 2031, in _build_and_run_instance
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] block_device_info=block_device_info)
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] File "/usr/lib/python2.7/dist-packages/nova/virt/libvirt/driver.py", line 3089, in spawn
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] destroy_disks_on_failure=True)
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] File "/usr/lib/python2.7/dist-packages/nova/virt/libvirt/driver.py", line 5607, in _create_domain_and_network
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] raise exception.VirtualInterfaceCreateException()
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b] VirtualInterfaceCreateException: Virtual Interface creation failed
2018-08-02 09:10:32.416 16204 ERROR nova.compute.manager [instance: b6e46303-3b86-4e14-8e18-d5d2725a854b]
解决方法：
/etc/nova/nova.conf编辑
[DEFAULT]
#Fail instance boot if vif plugging fails
vif_plugging_is_fatal = False
#Number of seconds to wait for neutron vif
#plugging events to arrive before continuing or failing
#(see vif_plugging_is_fatal). If this is set to zero and
#vif_plugging_is_fatal is False, events should not be expected to arrive at all.
vif_plugging_timeout = 0
