ARP Replies Intermittent for Floating IP Addresses

Seen when pinging external addresses using floating IP's and an external gateway.

Initial pings work, and they will keep working as long as you keep sending them.

However, if you stop the pings. Wait a while (a few minutes). Then try to ping again, it won't work. The problem is that we stop answering ARP requests.

Then, after a few minutes, we'll answer again.

[0] is a log is showing the time from when I sent the first ping to when it started working again.

[0] https://gist.github.com/anfredette/3048034b2a520db46ccea1613a20bd69

While it's not working, I see logs like this:
2016-09-16 09:32:24,652 | INFO | pool-16-thread-1 | ArpNotificationHandler | 341 - org.opendaylight.netvirt.vpnmanager-impl - 0.4.0.SNAPSHOT | Received ARP Request for interface 159202241306702:eth2:flat

Then, after I see this log:
2016-09-16 09:32:26,148 | INFO | ache Timer Tasks | ArpScheduler | 341 - org.opendaylight.netvirt.vpnmanager-impl - 0.4.0.SNAPSHOT | Removing the ARP cache forMacEntry [expiryTime=1474032745864, vpnName=c543f7d0-16d1-4155-ba68-4a0104bf6c86, macAddress=MacAddress [_value=fa:16:3e:04:b1:38], ipAddress=/192.168.56.10, interfaceName=53750758692350:eth2:flat]

It starts working again.