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Dell# show os-version
PoE-CONTROLLER IMAGE INFORMATION
---------------------------------------------------------------------
Type Version
PoE Controller 2.63
3 Verify the power details on the stack unit.
Dell#show power detail stack-unit 1
Dell#show power detail stack-unit 1
Unit Total System Redundancy Inline Inline Inline Inline Inline
Power Power Power Power Power Power Power Power
Available Consumed Consumed Threshold Available Allocated Consumed Remaining
(Watts) (Watts) (Watts) (%) (Watts) (Watts) (Watts) (Watts)
----------------------------------------------------------------------------------------
1 1100 150 0 99 940 0 0 940
Dell#
Manage Ports using Power Priority and Power Budget
The allocation and return of power on ports depends on the total inline power available in the system and the power priority calculation.
You can manage the power prioritization and the power allocation to the ports by using the power inline priority and power
budget
commands. For more information about the commands, see the Dell Networking OS Command Line Reference Guide.
Determine the Power Priority
Dell Networking OS uses a sophisticated port prioritization algorithm to determine which ports should receive power so that the PoE and
PoE+ ports are powered up and down deterministically.
Dell Networking OS uses the following four parameters for dening the power priority for a port:
1 Power inline mode: class or static.
2 Power inline priority conguration.
3 LLDP-MED priority sent by the PD in the Extended Power-via-MDI TLV or the priority sent by the PD in the IEEE 802.3at power-via-
mdi TLV.
4 Slot and port number.
Dell Networking OS maintains a sorted list of PoE/PoE+ ports based on the above parameters. The static ports have higher weight than
class mode ports. Hence all static ports always stay on top of all class ports, regardless of the other parameters. Within the set of static
ports, the Dell Networking OS attempts to order the ports based on the second parameter, power inline priority, the default of which is
Low. If the Dell Networking OS nds multiple ports with the same power-inline priority, it breaks the tie using the third parameter, the
LLDP-MED Priority or power-via-mdi priority the PD advertises, which can be Critical, High, or Low. If the Dell Networking OS still
nds a tie, the priority is based on the fourth parameter, which is the position of the port number in the switch. There cannot be a tie based
on this parameter.
The Dell Networking OS dynamically sorts this list when:
• The power-inline mode or priority changes.
• The PD advertises a dierent LLDP-MED priority or power-via-mdi priority
• The PD is connected or disconnected
The Dell Networking OS always uses this sorted list of ports for allocation. When you add an extra power supply unit (PSU), the additional
ports are powered based on this list. If you remove a PSU, the same list is used to remove power from the ports with lowest priority.
Power over Ethernet (PoE)
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