Extreme Networks ExtremeWare XOS 11.1, Manual

Page: 106 / 496

Power Over Ethernet
ExtremeWare XOS 11.1 Concepts Guide
106
port priority than those ports already receiving power). When you configure the deny-port value, the
switch disregards the configured PoE port priority and port numbering.
When the switch is configured for lowest-priority mode, PDs are denied power based on the port’s
configured PoE priority. If the next PD requesting power is of a higher configured PoE priority than an
already powered port, the lower-priority port is disconnected and the higher-priority port is powered.
To configure the disconnect precedence for the switch, use the following command:
configure inline-power disconnect-precedence [deny-port | lowest-priority]
To reset the disconnect precedence value to the default value of deny port to the switch, use the
following command:
unconfigure inline-power disconnect-precedence
PoE Port Priority
You can configure the PoE priority for each port as low, high, or critical; the default value is low. If you
configure the disconnect precedence of the switch as lowest priority, the switch disconnects those PDs
with lower PoE port priorities when the reserved slot power budget is exceeded; the system continues
supplying power to PDs with higher PoE port priorities.
To set the PoE port priority, use the following command:
configure inline-power priority [critical | high | low] ports <port_list>
To reset the PoE priority of the ports to the default value of low, use the following command:
unconfigure inline-power priority ports [all | <port_list>]
If several PDs have the same configured PoE port priority, the priority is determined by the port
number. The highest port number has the lowest PoE priority.
switch withdraws power (or disconnects) those ports with the highest port number (s). That is, the
highest port number is the lowest PoE priority.
Port Disconnect or Fault
When a port is disconnected, the power is removed from that port and can be used only by ports on the
same slot. The power from the disconnected port is not redistributed to any other slot.
When a port enters a fault state because of a class violation or if you set the operator limit lower than
the amount requested by the PD, the system removes power from that port. The power removed is,
again, available only to other ports on the same slot; it cannot be redistributed to other slots. The port
stays in the fault state until you disable that port, or disconnect the attached PD, or reconfigure the
operator limit to be high enough to satisfy the PD requirements.
To display the status of PoE ports, including disconnected or faulted ports, use the following command:
show inline-power info ports
When a port is disconnected or otherwise moves into a fault state, SNMP generates an event (once you
configure SNMP and a log message is created).