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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
 
Chapter 15      Configuring Power over Ethernet
Enhanced Power PoE Support on the E-Series Chassis
The default power inline configurations usually are sifficient; no additional configuration is required 
even for high power-consumption Cisco powered devices (for example, a Cisco AP1250 Wireless Access 
Point). When a high-power consumption device is attached to a port on a WS-X4648-RJ45V-E or 
WS-X4648-RJ45V+E line card, the switch and device negotiate power using CDP packets to 
automatically determine the extended amount of power needed by the device.
Depending on the deployment requirements and design, you specify a specific configuration with the 
power inline command. 
The following example shows how to pre-allocate PoE allocation to 16500 mW for Gi 2/1, regardless of 
what is mandated either by the 802.3af class of the discovered device or by any CDP packet that is 
received from the powered device:
Switch# configure terminal 
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface gigabitethernet 2/1
Switch(config-if)# power inline static max 16500
Switch(config-if)# end
Switch#
Configuring Universal PoE
Note This feature is only available on Supervisor Engine 7-E, Supervisor Engine 7L-E, and Supervisor Engine 
8-E.
Although IEEE 802.at only provides for power up to 30W per port, the WS-X4748-UPOE+E module can 
provide up to 60W using the spare pair of an RJ45 cable (wires 4,5,7,8) with the signal pair (wires 
1,2,3,6). Power on the spare pair is enabled when the switch port and end-device mutually identify 
themselves as Universal PoE (UPOE) capable using CDP or LLDP and the end-device requests for power 
on the spare pair to be enabled. When the spare pair is powered, the end-device can negotiate up to 60W 
power from the switch using CDP or LLDP. 
If the end-device is PoE capable on both signal and spare pairs but does not support the CDP or LLDP 
extensions required for UPOE, then the following configuration automatically enables power on both 
signal and spare pairs from the switch port:
Command Purpose
Step 1
Switch # interface terminal
Changes mode to global configuration.
Step 2
Switch(config)# interface {fastethernet | 
gigabitethernet} slot/port 
Selects the interface to configure.
Step 3
Switch(config-if)# power inline four-pair 
forced
To automatically enables power on both signal and spare 
pairs from a switch port.
Step 4
Switch(config-if)# shutdown
Shuts down the port.
Step 5
Switch(config-if)# no
Boots the port.
Step 6
Switch(config-if)# end 
Exits configuration mode.
Step 7
Switch# show platform software interface 
{fastethernet | gigabitethernet} slot/port 
status
Displays EEE status.