FCU upgrade from HFA40 to HFA60

[banduraj]

I'm testing this out (ClusterXL Full Connectivity Upgrade) in a lab environment to make sure it works right before I go forward with it on our gateways. For some reason, I can't get it to work. I have a gateway cluster setup hiding a desktop PC. I am RDP into the desktop PC which I have static NAT behind the cluster. From that PC, I am walking through the upgrade process to see if I get dropped, and I do every time. Maybe I'm missing something, here are the steps I am walking through. Cluster is new mode HA.

1) 'cphaconf set_ccp broadcast' on both gateways
2) upgrade the standby gateway
3) 'fw fcu <sync ip on old gateway>' on the upgraded gateway
4) 'cphastop; cpstop' on the old gateway (just after the cphastop, my connection bombs out
5) upgrade the last gateway
6) 'cphaconf set_ccp broadcast; cphastart' on both gateways

What am I missing here? From my understanding, my RDP session so transfer over smoothly with no issues.