How to assign the IP address to the BigIP system Interface ?

Steve,

With F5 devices, other than the MGMT interface, you don't assign ip addresses to a specific interface. Instead, IP addresses are associated with VLANs, where VLANs are groupings of interfaces.

Here's the relevant manual section for v11.2.

Hope that helps.

Steve, to find which ip address assigned to the interface you must find:

1. Vlan assigned to that interface in you case 1.7 -> go to Network / Vlans.
2. Go to Self IPs and find which ip address assigned to the Vlan.

To assign ip address to the interface:

1. Go to Network / Vlan and create a new one and assign to the interface for example 1.7.
2. Go to Network /Self IPs and create ip address and assign it to the new vlan.