LaCie ICA-312 User Manual page 98

The primary Ethernet port:
Carries the data when the LaCie 5big NAS Pro is configured in Fault Tolerance
Acts as the gateway to the internet when the LaCie 5big NAS Pro is connected to two separate networks
LAN interface and LaCie Network Assistant: LAN Port 1 must be enabled to use LaCie Network Assistant.
You can change the priority order by reassigning the role of primary port.
1. Click on the configuration icon (pencil) for the port you wish to assign as the primary.
2. Select Define as primary.
3. The star icon will move to the port to reflect the change.
LaCie 2big NAS (OS 3.0) | LaCie 5big NAS Pro User Manual 98