nova/api/openstack/compute/attach_interfaces.py

这个里面有很多个exception说为什么attach失败，但是没有打印到日志里面去，而是用http协议，返回到了客户端，或者是返回到了对应的服务器程序。

        try:
            vif = self.compute_api.attach_interface(context,
                instance, network_id, port_id, req_ip, tag=tag)
        except (exception.InterfaceAttachFailedNoNetwork,
                exception.NetworkAmbiguous,
                exception.NoMoreFixedIps,
                exception.PortNotUsable,
                exception.AttachInterfaceNotSupported,
                exception.SecurityGroupCannotBeApplied,
                exception.NetworkInterfaceTaggedAttachNotSupported,
                exception.NetworksWithQoSPolicyNotSupported,
                exception.InterfaceAttachPciClaimFailed,
                exception.InterfaceAttachResourceAllocationFailed,
                exception.ForbiddenPortsWithAccelerator,
                exception.ForbiddenWithRemoteManagedPorts,
                exception.ExtendedResourceRequestOldCompute,
                ) as e:
            raise exc.HTTPBadRequest(explanation=e.format_message())

需要看的日志是：
[cis2-1 (overcloudrc) httpd]$ ls
aodh-api cinder-api heat-api horizon manila-api nova-api nova-placement
barbican-api gnocchi-api heat-api-cfn keystone neutron-api nova-metadata panko-api