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Advertising Extended Power
The power device(PD) sends the information in the LLDP-MED extended power via MDI TLV and information in the IEEE 802.3 power via
MDI TLV.
Dell Networking OS uses the following information sent through LLDP-MED extended power-via-MDI TLV. The power is advertised using
the advertise med power-via-mdi command.
• Power Requirement — Used for power allocation.
• Power Priority — Used for priority calculation. The values are: Critical, High, Low.
• External Power Source — Not used.
Dell Networking OS uses the following information sent through IEEE 802.3 power-via-mdi TLV. The power is advertised using the
advertise dot3-tlv power-via-mdi command.
• Power Class — Displayed in the show power inline EXEC command. The PD-requested power value must be within the limits of the
maximum watts.
• Type — Displayed in the show power inline EXEC command and is used only when the PD is Type1 or Type2. The Type1 or Type2 PSE
requests are not used.
• Priority — Used for priority calculation.
• PD requested power value — Used for power allocation.
• PSE allocated power value — Used to check whether the PD is in sync with the PSE.
NOTE
: For more information about the advertise med power-via-mdi and advertise dot3-tlv power-via-mdi
commands, refer to the Dell Command Line Reference Guide .
Manage Inline Power
By default, PoE/PoE+ is disabled.
To manage the inline power supplied to the ports, use the power inline mode command in Conguration mode.
This command has the following parameters.
• class — When you congure class mode, the maximum power for the particular class of device is allocated. Class mode supports
power allocation through Layer 2 classication and power negotiation by the LLDP 802.3at standard. You can use this mode to
congure port priority.
• static — When you congure static mode, the inline power is allocated based on the actual power consumed by the powered
device. The power the PD requests is allocated and is reduced from the available pool. Power negotiation through LLDP (extended
power via MDI TLVs or IEEE 802.3 at power-via-mdi TLVs) is not supported in static mode. Ports you congure in Static mode reserve
a xed power allocation whether a device is connected or not. By default, 15.4 W is allocated for PoE and 30.0 W for PoE+. No dynamic
PoE/PoE+ class detection performs on Static ports. The default Power Management mode is static.
NOTE
: The power inline max_milliwatts command enables the inline power supplied to an interface. The
max_milliwatts option works only when you use Static mode. When you enable Class mode, the max_milliwatts
option has no eect on the interface. Instead, the maximum limit in Class mode applies to the ports.
• stack-unit unit-number — Specify the stack unit number. The range is from 1 to 12.
Set the Threshold Limit for the PoE Power Budget
To set the global threshold limit of the total power available for PoE on the port use the power budget global-threshold
stack-unit unit—number threshold-value command in Conguration mode.
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Power over Ethernet (PoE)