Concept Guide

93 | Customizing W-IAP Settings Dell Networking W-Series Instant 6.4.3.1-4.2.0.0 | User Guide
In the Instant UI
To change the USB port status:
1. From the Access Points tab, click the W-IAP to modify. The edit link is displayed.
2. Click the edit link. The edit window for modifying W-IAP details is displayed.
3. Click the Uplink tab.
4. Set the port status by selecting any of the following options:
l Disabled—To disable the port status.
l Enabled—To re-enable the port status.
5. Click OK.
6. Reboot the W-IAP.
In the CLI
To disable the USB port:
(Instant AP)# usb-port-disable
To re-enable the USB port:
(Instant AP)# no usb-port-disable
To view the USB port status:
(Instant AP)# show ap-env
Antenna Type:External
usb-port-disable:1
Master Election and Virtual Controller
Instant does not require an external mobility controller to regulate and manage the Wi-Fi network. Instead, one
W-IAP in every network assumes the role of Virtual Controller. It coordinates, stores, and distributes the
settings required to provide a centralized functionality to regulate and manage the Wi-Fi network. The Virtual
Controller is the single point of configuration and firmware management. When configured, the Virtual
Controller sets up and manages the VPN tunnel to a Mobility Controller in the data center.
The Virtual Controller also functions like any other AP with full RF scalability. It also acts as a node, coordinating
DHCP address allocation for network address translated clients ensuring mobility of the clients when they
roam between different W-IAPs.
Master Election Protocol
The Master Election Protocol enables the Instant network to dynamically elect a W-IAP to take on a Virtual
Controller role and allow graceful failover to a new Virtual Controller when the existing Virtual Controller is not
available. This protocol ensures stability of the network during initial startup or when the Virtual Controller
goes down by allowing only one W-IAP to self-elect as a Virtual Controller.
Preference to a W-IAP with 3G/4G Card
The Master Election Protocol prefers the W-IAP with a 3G/4G card, when electing a Virtual Controller for the
Instant network during the initial setup. The Virtual Controller is selected based on the following criteria:
l If there is more than one W-IAP with 3G/4G cards, one of these W-IAPs is dynamically elected as the Virtual
Controller.
l When a W-IAP without 3G/4G card is elected as the Virtual Controller but is up for less than 5 minutes,
another W-IAP with 3G/4G card in the network is elected as the Virtual Controller to replace it and the
previous Virtual Controller reboots.