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You can configure the LAN2 or LAN2 (VLAN) port to provide redundancy and additional fault tolerance in your network. Port redundancy is transparently supported for both IPv4 and IPv6. When you enable port redundancy, the LAN1 or LAN1 (VLAN) and LAN2 or LAN2 (VLAN) ports are grouped into one logical interface. They share one IP address and appear as one interface to the network. Then, if a link to one of the ports fails or is disabled, the appliance fails over to the other port, avoiding a service disruption.
You can connect the LAN1 or LAN1 (VLAN) and LAN2 or LAN2 (VLAN) ports to the same switch or to different switches, but they must be on the same VLAN configuration between LAN1 and LAN2 must match. One port is active and the other port is idle at all times. In case of failure in the LAN1 or LAN1 (VLAN) port, the LAN2 or LAN2 (VLAN) port becomes active and once the LAN1 or LAN1 (VLAN) port is active again, the LAN2 or LAN2 (VLAN) port becomes passive if the Use LAN1 when available option is enabled. For more information, see Enabling Port Redundancy.

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Enabling Port Redundancy

Before you enable port redundancy, ensure that both LAN1 and LAN2 are enabled. To enable port redundancy:

1. From the Grid tab, select the Grid Manager tab -> Members tab -> Grid_member check box, and then click the Edit icon.
2. In the Network -> Basic tab of the Grid Member Properties editor, select the Enable port redundancy on LAN/LAN2 check box.
3. Select the Use LAN1 when available check box to enable the NIOS appliance to automatically revert to the LAN1 port when it is available. In case of a connection failure, if the LAN1 port is not available, the NIOS appliance fails over to the LAN2 port. If you do not enable this option, the NIOS appliance will not automatically revert from the LAN2 port to the LAN1 port when it is available.
4. Save the configuration and click Restart if it appears at the top of the screen.

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