Dual-homing probing improvements
(1) Active probing mechanism in the following two scenarios
(1-1) Probe all ports on the pair device within the same vlan (excluding the pair port) when the 1st location of a host is learnt
(1-2) Probe again when a device/port goes down and comes up again
* Introduce HostLocationProvingService
- DISCOVER mode: discover potential new locations
- VERIFY mode: verify old locations
* Can be enabled/disabled via component config
* Improve HostHandlerTest to test the probing behavior
(2) Fix an issue that redirection flow doesn't get installed after device re-connects
(3) Temporarily fix a race condition in HostHandler by adding a little bit delay
Change-Id: I33d3fe94a6ca491a88b8e06f65bef11447ead0bf
6 files changed