Has any one configured Juniper SA in Dual-Port mode ? How does this work? Does that mean only 1 port will be used for both internal and external connections?
When you use both ports (two arm) then the internal and external connections are separated. You can use one port (one arm) and have both internal and external connections to the same port.
See kb10162 for a full description of all the deployment modes for the SSL VPN in both one arm and two arm modes.
http://kb.pulsesecure.net/InfoCenter/index?page=content&id=KB10162