Configuring PoE

Finding Feature Information

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Information About PoE

Power over Ethernet Ports

A PoE-capable switch port automatically supplies power to one of these connected devices if the device senses that there is no power on the circuit:

  • a Cisco pre-standard powered device (such as a Cisco IP Phone or a Cisco Aironet Access Point)

  • an IEEE 802.3af-compliant powered device

A powered device can receive redundant power when it is connected to a PoE switch port and to an AC power source. The device does not receive redundant power when it is only connected to the PoE port.

Supported Protocols and Standards

The device uses these protocols and standards to support PoE:

  • LLDP and CDP with power consumption—The powered device notifies the device of the amount of power it is consuming. The device does not reply to the power-consumption messages. The device can only supply power to or remove power from the PoE port.

  • Cisco intelligent power management—The powered device and the device negotiate through power-negotiation LLDP or CDP messages for an agreed-upon power-consumption level. The negotiation allows a high-power Cisco powered device, which consumes more than 7 W, to operate at its highest power mode. The powered device first boots up in low-power mode, consumes less than 7 W, and negotiates to obtain enough power to operate in high-power mode. The device changes to high-power mode only when it receives confirmation from the device.

    High-power devices can operate in low-power mode on devices that do not support power-negotiation LLDP or CDP.

    Cisco intelligent power management is backward-compatible with CDP with power consumption; the device responds according to the CDP message that it receives. CDP is not supported on third-party powered devices; therefore, the device uses the IEEE classification to determine the power usage of the device.

  • IEEE 802.3af—The major features of this standard are powered-device discovery, power administration, disconnect detection, and optional powered-device power classification. For more information, see the standard.

Powered-Device Detection and Initial Power Allocation

The device detects a Cisco pre-standard or an IEEE-compliant powered device when the PoE-capable port is in the no-shutdown state, PoE is enabled (the default), and the connected device is not being powered by an AC adaptor.

After device detection, the device determines the device power requirements based on its type:

  • The initial power allocation is the maximum amount of power that a powered device requires. The device initially allocates this amount of power when it detects and powers the powered device. As the device receives LLDP or CDP messages from the powered device and as the powered device negotiates power levels with the device through LLDP or CDP power-negotiation messages, the initial power allocation might be adjusted.

  • The device classifies the detected IEEE device within a power consumption class. Based on the available power in the power budget, the device determines if a port can be powered.

Table 1. IEEE Power Classifications

Class

Maximum Power Level Required from the Device

0 (class status unknown)

15.4 W

1

4 W

2

7 W

3

15.4 W

4

30 W (For IEEE 802.3at Type 2 powered devices)

The device monitors and tracks requests for power and grants power only when it is available. The device tracks its power budget (the amount of power available on the device for PoE). Thedevice performs power-accounting calculations when a port is granted or denied power to keep the power budget up to date.

After power is applied to the port, the device uses LLDP or CDP to determine the protocol-specific power consumption requirement of the connected Cisco powered devices, which is the amount of power to allocate based on the LLDP or CDP messages. The device adjusts the power budget accordingly. This does not apply to third-party PoE devices. The device processes a request and either grants or denies power. If the request is granted, the device updates the power budget. If the request is denied, the device ensures that power to the port is turned off, generates a syslog message, and updates the LEDs. Powered devices can also negotiate with the device for more power.

With PoE+, powered devices use IEEE 802.3at and LLDP power with media dependent interface (MDI) type, length, and value descriptions (TLVs), Power-via-MDI TLVs, for negotiating power up to 30 W. Cisco pre-standard devices and Cisco IEEE powered devices can use LLDP/CDP or the IEEE 802.3at power-via-MDI power negotiation mechanism to request power levels up to 30 W.


Note

The initial allocation for Class 0, Class 3, and Class 4 powered devices is 15.4 W. When a device starts up and uses CDP or LLDP to send a request for more than 15.4 W, it can be allocated up to the maximum of 30 W.

The protocol-specific (LLDP or CDP) power consumption requirement is referred to as the actual power consumption requirement in the software configuration guides and command references.

If the device detects a fault caused by an undervoltage, overvoltage, overtemperature, oscillator-fault, or short-circuit condition, it turns off power to the port, generates a syslog message, and updates the power budget and LEDs.

The PoE feature operates the same whether or not the device is a stack member. The power budget is per device and independent of any other device in the stack. Election of a new active device does not affect PoE operation. The active device keeps track of the PoE status for all devices and ports in the stack and includes the status in output displays.

Power Management Modes

The device supports these PoE modes:

  • auto —The device automatically detects if the connected device requires power. If the device discovers a powered device connected to the port and if the device has enough power, it grants power, updates the power budget, turns on power to the port on a first-come, first-served basis, and updates the LEDs. For LED information, see the hardware installation guide.

    If the device has enough power for all the powered devices, they all come up. If enough power is available for all powered devices connected to the device, power is turned on to all devices. If there is not enough available PoE, or if a device is disconnected and reconnected while other devices are waiting for power, it cannot be determined which devices are granted or are denied power.

    If granting power would exceed the system power budget, the device denies power, ensures that power to the port is turned off, generates a syslog message, and updates the LEDs. After power has been denied, the device periodically rechecks the power budget and continues to attempt to grant the request for power.

    If a device being powered by the device is then connected to wall power, the device might continue to power the device. The device might continue to report that it is still powering the device whether the device is being powered by the device or receiving power from an AC power source.

    If a powered device is removed, the device automatically detects the disconnect and removes power from the port. You can connect a nonpowered device without damaging it.

    You can specify the maximum wattage that is allowed on the port. If the IEEE class maximum wattage of the powered device is greater than the configured maximum value, the device does not provide power to the port. If the device powers a powered device, but the powered device later requests through LLDP or CDP messages more than the configured maximum value, the device removes power to the port. The power that was allocated to the powered device is reclaimed into the global power budget. If you do not specify a wattage, the device delivers the maximum value. Use the auto setting on any PoE port. The auto mode is the default setting.

  • static —The device pre-allocates power to the port (even when no powered device is connected) and guarantees that power will be available for the port. The device allocates the port configured maximum wattage, and the amount is never adjusted through the IEEE class or by LLDP/CDP messages from the powered device. Because power is pre-allocated, any powered device that uses less than or equal to the maximum wattage is guaranteed to be powered when it is connected to the static port. The port no longer participates in the first-come, first-served model.

    However, if the powered-device IEEE class is greater than the maximum wattage, the device does not supply power to it. If the device learns through LLDP or CDP messages that the powered device is consuming more than the maximum wattage, the device shuts down the powered device.


    Note

    In interface mode, the power consumption of a device cannot exceed the power supplied to the static port.

    If you do not specify a wattage, the device pre-allocates the maximum value. The device powers the port only if it discovers a powered device. Use the static setting on a high-priority interface.

  • never —The device disables powered-device detection and never powers the PoE port even if an unpowered device is connected. Use this mode only when you want to make sure that power is never applied to a PoE-capable port, making the port a data-only port.

For most situations, the default configuration (auto mode) works well, providing plug-and-play operation. No further configuration is required. However, perform this task to configure a PoE port for a higher priority, to make it data only, or to specify a maximum wattage to disallow high-power powered devices on a port.


Note

If static power is configured for a port, do not configure 2-event classfication. These two configurations will conflict with each other.

Power Monitoring and Power Policing

When policing of the real-time power consumption is enabled, the device takes action when a powered device consumes more power than the maximum amount allocated, also referred to as the cutoff-power value.

When PoE is enabled, the device senses the real-time power consumption of the powered device. The device monitors the real-time power consumption of the connected powered device; this is called power monitoring or power sensing. The device also polices the power usage with the power policing feature.

Power monitoring is backward-compatible with Cisco intelligent power management and CDP-based power consumption. It works with these features to ensure that the PoE port can supply power to the powered device.

The device senses the real-time power consumption of the connected device as follows:

  1. The device monitors the real-time power consumption on individual ports.

  2. The device records the power consumption, including peak power usage. The device reports the information through the CISCO-POWER-ETHERNET-EXT-MIB.

  3. If power policing is enabled, the device polices power usage by comparing the real-time power consumption to the maximum power allocated to the device. The maximum power consumption is also referred to as the cutoff power on a PoE port.

    If the device uses more than the maximum power allocation on the port, the device can either turn off power to the port, or the device can generate a syslog message and update the LEDs (the port LED is now blinking amber) while still providing power to the device based on the device configuration. By default, power-usage policing is disabled on all PoE ports.

    If error recovery from the PoE error-disabled state is enabled, the device automatically takes the PoE port out of the error-disabled state after the specified amount of time.

    If error recovery is disabled, you can manually re-enable the PoE port by using the shutdown and no shutdown interface configuration commands.

  4. If policing is disabled, no action occurs when the powered device consumes more than the maximum power allocation on the PoE port, which could adversely affect the device.

Maximum Power Allocation (Cutoff Power) on a PoE Port

When power policing is enabled, the device determines one of the these values as the cutoff power on the PoE port in this order:

  1. Manually when you set the user-defined power level that limits the power allowed on the port by using the power inline auto max max-wattage or the power inline static max max-wattage interface configuration command

  2. Automatically when the device sets the power usage of the device by using CDP power negotiation or by the IEEE classification and LLDP power negotiation.

Use the first or second method in the previous list to manually configure the cutoff-power value by entering the power inline consumption default wattage or the power inline [auto | static max] max-wattage command.

If you do not manually configure the cutoff-power value, the device automatically determines it by using CDP power negotiation or the device IEEE classification and LLDP power negotiation. If CDP or LLDP are not enabled, the default value of 30 W is applied. However without CDP or LLDP, the device does not allow devices to consume more than 15.4 W of power because values from 15400 to 30000 mW are only allocated based on CDP or LLDP requests. If a powered device consumes more than 15.4 W without CDP or LLDP negotiation, the device might be in violation of the maximum current (Imax) limitation and might experience an Icut fault for drawing more current than the maximum. The port remains in the fault state for a time before attempting to power on again. If the port continuously draws more than 15.4 W, the cycle repeats.


Note

When a powered device connected to a PoE+ port restarts and sends a CDP or LLDP packet with a power TLV, the device locks to the power-negotiation protocol of that first packet and does not respond to power requests from the other protocol. For example, if the device is locked to CDP, it does not provide power to devices that send LLDP requests. If CDP is disabled after the device has locked on it, the device does not respond to LLDP power requests and can no longer power on any accessories. In this case, you should restart the powered device.

Power Consumption Values

You can configure the initial power allocation and the maximum power allocation on a port. However, these values are only the configured values that determine when the device should turn on or turn off power on the PoE port. The maximum power allocation is not the same as the actual power consumption of the powered device. The actual cutoff power value that the device uses for power policing is not equal to the configured power value.

When power policing is enabled, the device polices the power usage at the switch port, which is greater than the power consumption of the device. When you manually set the maximum power allocation, you must consider the power loss over the cable from the switch port to the powered device. The cutoff power is the sum of the rated power consumption of the powered device and the worst-case power loss over the cable.

We recommend that you enable power policing when PoE is enabled on your device. For example, if policing is disabled and you set the cutoff-power value by using the power inline auto max 6300 interface configuration command, the configured maximum power allocation on the PoE port is 6.3 W (6300 mW). The device provides power to the connected devices on the port if the device needs up to 6.3 W. If the CDP-power negotiated value or the IEEE classification value exceeds the configured cutoff value, the device does not provide power to the connected device. After the device turns on power on the PoE port, the device does not police the real-time power consumption of the device, and the device can consume more power than the maximum allocated amount, which could adversely affect the device and the devices connected to the other PoE ports.


Note

In interface mode, the power consumption of a device cannot exceed the power supplied to the static port.

For example, if you configure power supply to the port at 6000 mW (power inline static6000 interface configuration command), do not configure power consumption by a device at 8000 mW on the same port (power inline consumption8000 interface configuration command).

Fast POE

This feature remembers the last power drawn from a particular PSE port and switches on power the moment AC power is plugged in (within 15 to 20 seconds of switching on power) without waiting for IOS to boot up. When poe-ha is enabled on a particular port, the switch on a recovery after power failure, provides power to the connected endpoint devices within short duration before even the IOS forwarding starts up.

This feature can be configured by the same command as poe-ha which is already implemented. If the user replaces the power device connected to a port when the switch is powered off, then this new device will get the power which the previous device was drawing.


Note
In case of UPOE, even though Fast POE is available on the switch side, the PD endpoints may not be able to take advantage of the same, due to the reliance on LLDP to signal the UPOE power availability. This reliance on LLDP requires that the PD endpoint still needs to wait till the IOS comes up and LLDP packet exchanges can happen, signaling the availability of UPOE power.

Perpetual POE

The Perpetual POE provides uninterrupted power to connected PD device even when the PSE switch is booting.


Note
Power to the ports will be interrupted in case of MCU firmware upgrade and ports will be back up immediately after the upgrade.

Cisco Universal Power Over Ethernet

Cisco Universal Power Over Ethernet (Cisco UPOE) is a Cisco proprietary technology that extends the IEEE 802.at PoE standard to provide the capability to source up to 60 W of power over standard Ethernet cabling infrastructure (Class D or better) by using the spare pair of an RJ-45 cable (wires 4,5,7,8) with the signal pair (wires 1,2,3,6). Power on the spare pair is enabled when the switch port and end device mutually identify themselves as Cisco UPOE-capable using CDP or LLDP and the end device requests for power to be enabled on the spare pair. When the spare pair is powered, the end device can negotiate up to 60 W of power from the switch using CDP or LLDP.

If the end device is PoE-capable on both signal and spare pairs but does not support the CDP or LLDP extensions required for Cisco UPOE, a 4-pair forced mode configuration automatically enables power on both signal and spare pairs from the switch port.

Fast UPOE and Perpetual UPOE

The Cisco Digital Building Switches support enhanced versions of Cisco Universal Power over Ethernet (UPOE) in the form of Fast UPOE and Perpetual UPOE.

  • Fast UPOE: Fast UPOE allows the switch to provide the prenegotiated PoE or UPOE power to a powered-down device within 5 seconds of power restoration. This ensures that devices can power up quickly after a power outage.

  • Perpetual UPOE: Perpetual UPOE provides uninterrupted power to a powered-down device even when the switch is booting. You can connect any PoE-powered device (for example, a light fixture or IP surveillance camera) to the switch port and reload the switch. The PoE-powered device will continue to work and get last negotiated power.

Configuring Deep Sleep

Deep Sleep is a power saving feature that puts the switch into hibernation mode. In this mode, the switch draws very little power. All connected devices also stop drawing power from the switch.

You can configure certain triggers that will put the switch into Deep Sleep mode. Similarly, the switch can wake up from Deep Sleep mode upon certain triggers.

How to Configure PoE

Configuring a Power Management Mode on a PoE Port


Note

When you make PoE configuration changes, the port being configured drops power. Depending on the new configuration, the state of the other PoE ports, and the state of the power budget, the port might not be powered up again. For example, port 1 is in the auto and on state, and you configure it for static mode. The device removes power from port 1, detects the powered device, and repowers the port. If port 1 is in the auto and on state and you configure it with a maximum wattage of 10 W, the device removes power from the port and then redetects the powered device. The device repowers the port only if the powered device is a class 1, class 2, or a Cisco-only powered device.

SUMMARY STEPS

  1. enable
  2. configure terminal
  3. interface interface-id
  4. power inline {auto [max max-wattage] | never | static [max max-wattage]}
  5. end
  6. show power inline [interface-id | module switch-number]
  7. copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose

Step 1

enable

Example:


Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

configure terminal

Example:

Device# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Device(config)# interface gigabitethernet 0/1

Specifies the physical port to be configured, and enters interface configuration mode.

Step 4

power inline {auto [max max-wattage] | never | static [max max-wattage]}

Example:

Device(config-if)# power inline auto

Configures the PoE mode on the port. The keywords have these meanings:

  • auto —Enables powered-device detection. If enough power is available, automatically allocates power to the PoE port after device detection. This is the default setting.

  • max max-wattage —Limits the power allowed on the port. The range is 4000 to 30000 mW. If no value is specified, the maximum is allowed.

  • never —Disables device detection, and disable power to the port.

Note

 

If a port has a Cisco powered device connected to it, do not use the power inline never command to configure the port. A false link-up can occur, placing the port into the error-disabled state.

  • static —Enables powered-device detection. Pre-allocate (reserve) power for a port before the device discovers the powered device. The device reserves power for this port even when no device is connected and guarantees that power will be provided upon device detection.

Note

 

Configure power values in multiples of 100. For example, you can configure 7400 mW, but do not configure 7386 mW or 7421 mW.

The device allocates power to a port configured in static mode before it allocates power to a port configured in auto mode.

Step 5

end

Example:

Device(config-if)# end

Returns to privileged EXEC mode.

Step 6

show power inline [interface-id | module switch-number]

Example:

Device# show power inline

Displays PoE status for a device or a device stack, for the specified interface, or for a specified stack member..

The module switch-number keywords are supported only on stacking-capable devices.

Step 7

copy running-config startup-config

Example:


Device# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Power Policing

By default, the device monitors the real-time power consumption of connected powered devices. You can configure the device to police the power usage. By default, policing is disabled.


Note

The power consumption is displayed in units of 0.5 W. For example, if a connected device draws 3.9 W, this feature will display 4.0 W power drawn.

SUMMARY STEPS

  1. enable
  2. configure terminal
  3. interface interface-id
  4. power inline police [action{log | errdisable}]
  5. exit
  6. Use one of the following:
    • errdisable detect cause inline-power
    • errdisable recovery cause inline-power
    • errdisable recovery interval interval
  7. exit
  8. Use one of the following:
    • show power inline police
    • show errdisable recovery
  9. copy running-config startup-config

DETAILED STEPS

  Command or Action Purpose

Step 1

enable

Example:


Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

configure terminal

Example:

Device# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Device(config)# interface gigabitethernet 0/1

Specifies the physical port to be configured, and enter interface configuration mode.

Step 4

power inline police [action{log | errdisable}]

Example:

Device(config-if)# power inline police

If the real-time power consumption exceeds the maximum power allocation on the port, configures the device to take one of these actions:

  • power inline police —Shuts down the PoE port, turns off power to it, and puts it in the error-disabled state.

Note

 

You can enable error detection for the PoE error-disabled cause by using the errdisable detect cause inline-power global configuration command. You can also enable the timer to recover from the PoE error-disabled state by using the errdisable recovery cause inline-power interval interval global configuration command.

  • power inline police action errdisable —Turns off power to the port if the real-time power consumption exceeds the maximum power allocation on the port.

  • power inline police action log —Generates a syslog message while still providing power to the port.

If you do not enter the action log keywords, the default action shuts down the port and puts the port in the error-disabled state.

Step 5

exit

Example:

Device(config-if)# exit

Returns to global configuration mode.

Step 6

Use one of the following:

  • errdisable detect cause inline-power
  • errdisable recovery cause inline-power
  • errdisable recovery interval interval

Example:

Device(config)# errdisable detect cause inline-power


Device(config)# errdisable recovery cause inline-power


Device(config)# errdisable recovery interval 100

(Optional) Enables error recovery from the PoE error-disabled state, and configures the PoE recover mechanism variables.

By default, the recovery interval is 300 seconds.

For interval interval , specifies the time in seconds to recover from the error-disabled state. The range is 30 to 86400.

Step 7

exit

Example:

Device(config)# exit

Returns to privileged EXEC mode.

Step 8

Use one of the following:

  • show power inline police
  • show errdisable recovery

Example:

Device# show power inline police


Device# show errdisable recovery

Displays the power monitoring status, and verify the error recovery settings.

Step 9

copy running-config startup-config

Example:


Device# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Fast PoE

To configure Fast PoE, perform the following steps:


Note

You will need to configure the poe-ha command before connecting the PD, or you will need to manually shut/unshut the port after configuring poe-ha .

SUMMARY STEPS

  1. enable
  2. configure terminal
  3. interface interface-id
  4. power inline port poe-ha
  5. end

DETAILED STEPS

  Command or Action Purpose

Step 1

enable

Example:


Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

configure terminal

Example:


Device# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Device(config)# interface gigabitethernet2/0/1

Specifies the physical port to be configured, and enters interface configuration mode.

Step 4

power inline port poe-ha

Example:


Device(config-if)# power inline port poe-ha

Configures POE High Availability.

Step 5

end

Example:


Device(config-if)# end

Returns to privileged EXEC mode.

How to Configure Deep Sleep

This section explains how to configure the various triggers that will put the switch into Deep Sleep mode and wake up the switch from Deep Sleep Mode.

Configuring the Switch to Enter Deep Sleep Mode

You can configure several triggers that will put the switch into Deep Sleep mode.

  • Using EnergyWise to hibernate the switch at a specified time

  • A COAP CLI command

  • A COAP command over HTTP that sends a payload data packet to the switch

  • Using the SNMP 'set-request' operation, which hibernates the switch immediately when it receives an authentic SNMP message.

Using EnergyWise

You can use an EnergyWise Level 1 command to put the switch into hibernation mode automatically at a specified time. This will use the real-time clock that runs on the switch. This hibernation mode will cause the switch to enter Deep Sleep mode.

You can also use an EnergyWise level 1 command to put the switch into Deep Sleep mode immediately. To do this, provide the time in CRON format (instead of a time range). For example, enter the following: 

Switch(config)#energywise level 1 recurrence importance 100 at 20 14 31 5 4
where

20 - Minutes

14 - Hours

31 - Day

5 - Month

4 - (No significance. But a value is required; can range from 0-7)

The Switch will enter Deep Sleep immediately after the command is given, and will wake up at 14:20 31st of May of the current year.

For details on using the EnergyWise Level 1 command, see the section in the Configuring Hibernation Start and End Times chapter of this book.

COAP CLI Command

You can use a COAP command to put the switch into Deep Sleep mode immediately.

In the global configuration mode, enter the following command.

Command

Purpose

Switch(Config)#coap sleep wol{enable | disable}

Puts the switch immediately into Deep Sleep Mode.

  • enable— The switch will listen for incoming packets in the uplink ports in order to wake up.

  • disable— The switch cannot be woken up from packets sent to the uplink ports. In this case, the only way to wake up the switch is to press the MODE button.

Send Payload Data

You can configure the switch to enter Deep Sleep mode when a packet of data (payload) is sent to the switch. This packet is sent via COAP over HTTP.

  • Step 1: Use a REST client and connect to the switch by going to the URL http://<Switch IP>/level/15/coap/cisco/sleep.

  • Step 2: POST with payload 'data={“WOL”:1}'

Enter "WOL:1" if you want the switch to listen for incoming packets in the uplink ports in order to wake up.

Enter "WOL:0" if you do not want the switch to listen for incoming packets in the uplink ports in order to wake up. In this case, the only way to wake up the switch is to press the MODE button.

Using SNMP 'set-request' operation

You can send a 'set-request' message from the SNMP (Simple Network Management Protocol) manager to the SNMP agent on the switch to put it into Deep Sleep mode immediately. The switch will wake up from Deep Sleep at the time specified in the request.

  • Operation: set-request

  • MIB: CISCO-ENERGYWISE-MIB

  • MIB table for the operation: cewEventEntry


Note

Deep Sleep using the SNMP method can be enabled only on Catalyst switches that support the Cisco Digital Building architecture.

The following object IDs in the MIB table are applicable:

  • cewEventLevel—Format must be the integer of 2

  • cewEventImportance—Format must be an unsigned integer between 1 to 100

  • cewEventTime—Format must be a octal string

  • cewEventStatus—Format must be the integer value of 4


Note

For the entPhysical index, specify 1001 for switch. For the cewEvent index, specify 1.

For example, if you are sending the request from a Linux device, enter the following:
snmpset -mALL -v2c -cpublic 10.106.18.102 cewEventLevel.1001.1 i 2 cewEventImportance.1001.1 u 100 cewEventTime.1001.1 x " 34 35 20 39 20 33 30 20 35 " cewEventStatus.1001.1 i 4
where the cewEventTime.1001.1 x " 34 35 20 39 20 33 30 20 35 " is mentioned as an octal string of 34 35 20 39 20 33 30 20 35 which translates into the string equivalent of 45 9 30 5; thus, translating into 09:45 30th-May of the current year.

Configuring the Switch to Wake Up From Deep Sleep Mode

You can configure several triggers that will wake up the switch from Deep Sleep mode.

Triggers that wake up the switch from Deep Sleep mode are:

  • Using EnergyWise to wake up the switch at a specified time

  • A COAP command that sends a payload data packet to the switch

  • Using the SNMP 'set-request' operation to wake up the switch at a specified time

  • Pressing the MODE button on the switch

Using EnergyWise

If you have configured an EnergyWise Level 1 command to put the switch into Deep Sleep mode at a specified time, the same configuration is used to wake up the switch at a specified time. This will use the real-time clock that runs on the switch.

Send Payload Data

You can configure the switch to wake up from Deep Sleep mode when a packet of data (payload) is sent to the switch. This packet is sent via COAP.

  • Step 1: Use a REST client and connect to the switch by going to the URL coap://<switch IP>/cisco/sleep.

  • Step 2: POST with payload '{"level":"10"}'

Using SNMP 'set-request' operation

If you have configured Deep Sleep using the SNMP 'set-request' operation, then the switch will wake up from hibernation at the time specified in this operation.

MODE Button

Press and hold the MODE button on the switch for 5 seconds to wake up the switch from Deep Sleep mode. If you have configured the switch to wake up from hiberation at a specified time, you can use the MODE button to wake up the switch earlier than the scheduled time.

Monitoring Power Status

Table 2. Show Commands for Power Status

Command

Purpose

show env power switch [switch-number]

(Optional) Displays the status of the internal power supplies for each switch in the stack or for the specified switch.

The range is 1 to , depending on the switch member numbers in the stack. These keywords are available only on stacking-capable switches.

show power inline [interface-id | module switch-number]

Displays PoE status for a switch or switch stack, for an interface, or for a specific switch in the stack.

show power inline police

Displays the power policing data.


Note

Use thedebug ilpower controller privileged EXEC command to enable debugging of the platform-specific Power over Ethernet (PoE) software module on the switch in long message format. These messages include the Power Controller register reading. Use the no form of this command to disable debugging.

Configuration Examples for Configuring PoE

Budgeting Power: Example

When you enter one of the following commands,

  • [no] power inline consumption default wattage global configuration command

  • [no] power inline consumption wattage

    interface configuration command

this caution message appears:


%CAUTION: Interface Gi1/0/1: Misconfiguring the 'power inline  consumption/allocation' command may cause damage to the 
switch and void your warranty. Take precaution not to oversubscribe the power supply. It is recommended to enable power 
policing if the switch supports it. Refer to documentation.

Example: Configuring Perpetual PoE

This example shows how you can configure perpetual POE on the switch. 

Device> enable
Device# configure terminal
Device(config)# interface gigabitethernet2/0/1 
Device(config-if)# power inline port poe-ha
Device(config-if)# end