"keepalived_state_change" monitor does not use eventlet but normal Python threads. When "send_ip_addr_adv_notif" is called from inside the monitor, the arping command is never sent because the eventlet thread does not start. In order to be able to be called from this process, this method should also have an alternative implementation using "threading".
This should have been captured by "TestMonitorDaemon.test_new_fip_sends_garp", but there is a problem in the implementation of this test. This test created two namespaces with a veth interface connecting both. The "keepalived_state_change" monitor is set to capture the events in the first namespace and the interface created inside. The test expects the monitor to send a GARP when a new IP address is added to the monitored interface. But this agent does not send a GARP from the monitored interface if a new IP address is set but from any other interface in this namespace [1].
This test use to pass because when the "ip neigh" is checked the second time, the "expected_ip" address is in the second namespace ARP table. This is because when the test asserts there is no ping and then sets the IP address on the interface, the last ping is replied by the interface:
http://paste.openstack.org/show/791516/
This will, not intentionally, populate the ARP table in the second namespace but the GARP was not sent by the "keepalived_state_change" monitor.
[1] https://github.com/openstack/neutron/blob/8ee34655b8757086c03feecfda100333f47ed810/neutron/agent/l3/keepalived_state_change.py#L90
Fix proposed to branch: master
Review: https:/