Allied Telesis AT 8000/8POE - Manual (Page 34)

Chapter 3: Basic Switch Parameters
34 Section I: Using the Menus Interface
b. Enter the subnet mask for the switch.
5. To set the switch’s gateway address, do the following:
a. Type G to select Set Default Gateway.
The following prompt is displayed:
Enter new gateway IP address>
b. Enter the gateway IP address for the switch.