Comment 0 for bug 1845354

In "FdbInterfaceTestCase" test cases (no namespace scenario), can happen that two test cases are creating VXLAN interfaces in the kernel namespace (VTI) in the same VTEP and the same destination port (default=4789). In this case, the kernel will raise the exception errno.EEXIST (file already exists).

In order to avoid this problem, a random VNI could be used when creating the VXLAN interfaces.

How to test this:

from neutron.agent.linux import ip_lib
from neutron.privileged.agent.linux import ip_lib as priv_ip_lib
ns_name = 'ns_test'
try:
    priv_ip_lib.remove_netns(ns_name)
except:
    pass
priv_ip_lib.create_netns(ns_name)
dev = 'device'
dev2 = 'device2'
dev_vxlan = 'device_vxlan'
dev_vxlan2 = 'device_vxlan2'
ip_wrapper = ip_lib.IPWrapper(ns_name)
ip_wrapper.add_dummy(dev)
ip_wrapper.add_dummy(dev2)
ip_device1 = ip_lib.IPDevice(dev, ns_name)
ip_device2 = ip_lib.IPDevice(dev2, ns_name)
ip_device1.link.set_up()
ip_device2.link.set_up()
ip_wrapper.add_vxlan(dev_vxlan, 100, dev=dev)
try:
    ip_wrapper.add_vxlan(dev_vxlan2, 100, dev=dev2)
except Exception as e:
    print(str(e))
priv_ip_lib.remove_netns(ns_name)