Extreme Networks ExtremeWare XOS 11.3, Manual

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Power Over Ethernet
ExtremeWare XOS 11.3 Concepts Guide
164
Power Checking for PoE Module
PoE modules require more power than other I/O modules. When a chassis containing a PoE module is
booted or a new PoE module is inserted, the power drain is calculated. Before the PoE module is
powered up, the chassis calculates the power budget and powers up the PoE module only if there is
enough power. The chassis powers up as many I/O modules as possible with lower-numbered slots
having priority.
NOTE
If your chassis has an inline power module and there is not enough power to supply the configured inline power for
the slot, that slot will not power on; the slot will not function in data-only mode without enough power for inline
power.
If a PoE module is inserted into a chassis, the chassis calculates the power budget and only powers up
the PoE module if there is enough power. Installed modules are not affected. However, if you reboot the
chassis, power checking proceeds as described in the previous paragraph. If there is now enough power,
I/O modules that were not powered up previously are powered up.
If you lose power or the overall available power decreases, the system removes power to the I/O
modules beginning with the highest numbered slots until enough power is available. Inline power
reserved for a slot that is not used cannot be used by other PoE slots (inline power is not shared among
PoE modules).
Before you install your PoE module, consult your sales team to determine the required power budget.
Power Delivery
This section discusses how the system provides power to the PDs.
Enabling PoE to the Switch
You enable or disable inline power to the entire switch, or per slot or per port. Then you must reserve
power for each PoE Slot (refer to
“Power Reserve Budget Per Slot” ). By default, 50 watts of inline power
is provided to each slot.
To enable inline power to the switch, slot, or port, use the following commands:
enable inline-power
To disable inline power to the switch, use the following command:
disable inline-power
Disabling inline power removes power immediately to all connected PDs. The default value is enabled.
Power Reserve Budget Per Slot
The power budget is provided on a per slot basis, not switchwide. You reserve power for each slot, or
PoE module. Power reserved for a specific PoE module cannot be used by any other slot regardless of