158
Power over Ethernet
•
a device is connected to port 41 and requests power
In this scenario, the Nortel Ethernet Routing Switch 4548GT-PWR provides
power to the device on port 41 because that port is configured as high
priority. However, to maintain the power budget, the switch drops one of
the ports configured as low priority. As all the other ports (1 to 40) are
configured with a low priority, the switch drops power to the highest port
number. In this case, the switch drops power to port 40 and provides power
to port 41. If another port drops power, the switch automatically reinstates
power to port 40.
You configure the autodiscovery power process as either IEEE
802.3af-compliant or IEEE 802.3af-draft-compliant and legacy:
•
802.3af: detection method described in the IEEE 802.3af draft standard
•
legacy: detection standard in use prior to the IEEE 802.3af draft
standard
The default value is IEEE 802.3af-draft-compliant. You can set this
parameter for the entire switch; you cannot set the discovery mode for each
port.
You can obtain power usage information from the management systems.
Statistics do not accumulate. The system automatically disconnects the port
from power when it detects an overload on any port, and the remainder of
the ports remain functional.
Note: Ensure that you set the switch for the power- detection mode used
by the connected powered device. Consult the device documentation
for this information.
Configuring PoE using the CLI
The following section describes the commands necessary to configure PoE
using the CLI:
•
"Set port power enable or disable" (page 159)
•
"Set port power priority" (page 159)
•
"Set power limit for channels" (page 159)
•
"Set traps control" (page 160)
•
"Show main power status" (page 160)
•
"Set power usage threshold" (page 160)
•
"Setting PoE detection method" (page 161)
•
"Show port power status" (page 161)
•
"Show port power measurement" (page 161)
Nortel Ethernet Routing Switch 4500 Series
Overview — System Configuration
NN47205-500
02.01
Standard
5.0
23 February 2007
Copyright © 2007, Nortel Networks
Nortel Networks Confidential
.
