An ION device has one or two controller ports.
You are allowed to configure two controller ports from
Release
5.2.1
. In a virtual interface, you can use both the controller
ports to establish redundancy in controller connectivity. The controller
ports can thus be in the same subnet. Controller port is by default
used as source interface for controller connections and in the absence
of controller port, the device automatically picks any L3 port as
source interface for controller connections. If you plan to use
the controller port, connect to existing LAN segment with Internet
reachability.