- Index
- Preface
- Product Overview
- Command-Line Interfaces
- Configuring the Switch for the First Time
- Configuring Interfaces
- Checking Port Status and Connectivity
- Configuring Supervisor Engine Redundancy using RPR and SSO
- Environmental Monitoring and Power Management
- Configuring Power over Ethernet
- Managing a Network of Switches
- Understanding and Configuring VLANs
- Configuring Dynamic VLAN Membership
- Configuring Layer 2 Ethernet Interfaces
- Configuring SmartPort Macros
- Understanding and Configuring STP
- Configuring STP Features
- Understanding and Configuring Multiple Spanning Trees
- Understanding and Configuring EtherChannel
- Configuring IGMP Snooping and Filtering
- Configuring 802.1Q and Layer 2 Protocol Tunneling
- Understanding and Configuring CDP
- Configuring UDLD
- Configuring Unidirectional Ethernet
- Configuring Layer 3 Interfaces
- Configuring Cisco Express Forwarding
- Understanding and Configuring IP Multicast
- Configuring Policy-Based Routing
- Understanding and Configuring VTP
- Configuring VRF-lite
- Configuring QoS
- Configuring Voice Interfaces
- Understanding and Configuring 802.1X Port-Based Authentication
- Configuring Port Security
- Configuring DHCP Snooping and IP Source Guard
- Understanding and Configuring Dynamic ARP Inspection
- Configuring Network Security with ACLs
- Configuring Private VLANs
- Port Unicast and Multicast Flood Blocking
- Configuring Port-Based Traffic Control
- Configuring SPAN and RSPAN
- Configuring NetFlow Statistics Collection
- Acronyms
Configuring Power over Ethernet
Note 
Before reading this chapter, read "Preparing for Installation" section of the
Catalyst 4500 Series Installation Guide. It is important to ensure that your installation site has enough power and cooling to accommodate the additional electrical load and heat introduced by PoE.
This chapter describes how to configure Power over Ethernet (PoE) on the Catalyst 4500 series switch.
This chapter contains the following sections:
•Configuring Power Consumption for Powered Devices on an Interface
•Displaying the Operational Status for an Interface
•Displaying the PoE Consumed by a Module
Catalyst 4500 series switches can sense if a powered device is connected to a PoE module. They can supply PoE to the powered device if there is no power on the circuit. (If there is power on the circuit, the switch does not supply it.) The powered device can also be connected to an AC power source and supply its own power to the voice circuit.
Note A powered device is any device connected to the switch that requires external power or can utilize PoE, for example, an access point or Cisco IP phone.
Note For complete syntax and usage information for the switch commands used in this chapter, refer to the Catalyst 4500 Series Switch Cisco IOS Command Reference and related publications at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/index.htm.
Power Management Modes
If your switch has a module capable of providing PoE to end stations, you can set each interface on the module to automatically detect and apply PoE if the end station requires power.
The Catalyst 4500 series switch has three PoE modes:
•auto—PoE interface. The supervisor engine directs the switching module to power up the interface only if the switching module discovers the phone and the switch has enough power. You can specify the maximum wattage that is allowed on the interface. If you do not specify a wattage, then the switch will deliver no more than the hardware-supported maximum value. This mode has no effect if the interface is not capable of providing PoE.
•static—High priority PoE interface. The supervisor engine preallocates power to the interface, even when nothing is connected, guaranteeing that there will be power for the interface. You can specify the maximum wattage that is allowed on the interface. If you do not specify a wattage, then the switch preallocates the hardware-supported maximum value. If the switch does not have enough power for the allocation, the command will fail. The supervisor engine directs the switching module to power up the interface only if the switching module discovers the powered device.
•never—Data interface only The supervisor engine never powers up the interface, even if an unpowered phone is connected. This mode is only needed when you want to make sure power is never applied to a PoE-capable interface.
The switch can measure the actual PoE consumption for an 802.3af-compliant PoE module, and displays this in the show power module command. However, it cannot display the consumption of an individual interface on an 802.3af-compliant PoE module.
PoE consumption cannot be measured on the WS-X4148-RJ45V PoE module. Therefore, for all PoE calculations, the PoE consumption on this module is presumed to be equal to its administrative PoE.
For more information, see the "Displaying the PoE Consumed by a Module" section.
For most users, the default configuration of "auto" works well, providing plug and play capability. No further configuration is required. However, to make an interface higher priority or data only, or to specify a maximum wattage, perform this task:
If you set a non-PoE-capable interface to automatically detect and apply power, an error message indicates that the configuration is not valid.
The following example shows how to set the Fast Ethernet interface 4/1 to automatically detect PoE and send power through that interface:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface fastethernet 4/1
Switch(config-if)# power inline auto
Switch(config-if)# end
This example shows how to verify the PoE configuration for the Fast Ethernet interface 4/1:
Switch# show power inline fastethernet 4/1
Available:677(w) Used:11(w) Remaining:666(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Fa4/1 auto on 11.2 10.0 Ieee PD 0
Interface AdminPowerMax AdminConsumption
(Watts) (Watts)
---------- --------------- --------------------
Fa4/1 15.4 10.0
Switch#
The following example shows how to configure an interface so that it never supplies power through the interface:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface fastethernet 5/2
Switch(config-if)# power inline never
Switch(config-if)# end
Switch#
Configuring Power Consumption for Powered Devices on an Interface
This section contains the following subsections:
•PoE and Supported Cabling Topology
Overview
By default, when the switch detects a powered device on an interface, it assumes the powered device consumes the maximum the port can provide (7 W on a legacy Power over Ethernet (PoE) module and 15.4W on the IEEE PoE modules introduced in Release 12.2(18)EW). Then, when the switch receives a CDP packet from the powered device, the wattage automatically adjusts downward to the specific amount required by that device. Normally, this automatic adjustment works well, and no further configuration is required or recommended. However, you can specify the powered device's consumption for the entire switch (or for a particular interface) to provide extra functionality from your switch. This is useful when CDP is disabled or not available.
Note When manually configuring the consumption for powered devices, you need to account for the power loss over the cable between the switch and the powered device.
To change the power consumption for the entire switch, perform this task:
This example shows how to set the default PoE consumption of all powered devices connected to the switch to 5000 milliwatts:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# power inline consumption default 5000
Switch(config)# end
Switch#
This example shows how to verify the PoE consumption:
Switch# show power inline consumption default
Default PD consumption : 5000 mW
Switch#
To change the power consumption of a single powered device, perform this task:
This example shows how to set the PoE consumption to 5000 milliwatts for Fast Ethernet interface 4/1 regardless what is mandated by the 802.3af class of the discovered device, or by any CDP packet received from the powered device:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface fastethernet 4/1
Switch(config-if)# power inline consumption 5000
Switch(config-if)# end
Switch#
This example shows how to verify the PoE consumption for a given interface:
Switch# show power inline fastethernet 4/1
Available:677(w) Used:11(w) Remaining:666(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Fa4/1 auto on 11.2 10.0 Ieee PD 0
Interface AdminPowerMax AdminConsumption
(Watts) (Watts)
---------- --------------- --------------------
Fa4/1 15.4 10.0
Switch#
Intelligent Power Management
All Catalyst 4500 PoE-capable modules use Intelligent Power Management to provision power on each interface. When a powered device (PD) is attached to a PoE-capable port, the port will detect the PD and provision power accordingly. If a Cisco PD is used, the switch and PD negotiate power using CDP packets to determine the precise amount of power needed by the PD. If the PD is 802.3af compatible, the difference between what is mandated by the 802.3af class and what is actually needed by the PD is returned to the power budget for use by additional devices. In this way, power negotiation allows customers to stretch their power budget and use it more effectively.
Power negotiation also enables the interoperability of newer Cisco powered devices with older legacy PoE-capable ports from Cisco. Newer Cisco PDs do not consume more than what the switch port can provide.
PoE and Supported Cabling Topology
When using PoE, pairs 2 and 3 (pins 1, 2, 3, and 6) of the four pairs in a standard UTP cable are used for both the Ethernet data signals and the DC power at the same time. In DC, PoE flows from pair 3 (pins 3 and 6) to the device using PoE and back to pair 2 (pins 1 and 2) while the Ethernet port transmits differential signals in pair 2 (between pins 1 and 2). This method of supplying DC power is sometimes called "phantom power" because the power signals travel over the same two pairs used to transmit Ethernet signals. The inline power signals are transparent to the Ethernet signals and do not interfere with each other. The main electrical parameter that affects inline power operation and performance is the DC resistance of the cable. The inline power method is designed to work with category 3 cable and above, up to 100 meters.
PoE has been tested and found to work with the IBM Token Ring STP cable (100 meters) when used with a Token Ring to Fast Ethernet adapter.
When you use PoE modules with type 1/2 shielded twisted pair (STP) cable configurations ( 90 and 125 meters), the modules perform the same as with Category 5 cable for the IEEE 802.3af standard at 10 and 100 Mb/s.
The following adapters have been tested and known to work properly with Catalyst 4500 PoE modules:
•LanTel Silver Bullet (SB-LN/VIP-DATA adapter)
•BIP-1236/S (BATM)
•RIT P/N 13712017
•RIT balun with integrated unshielded twisted pair (UTP) cable, 6 and 24 foot lengths
The following topology is supported:
Figure 8-1 Supported Adapter Topology
In Figure 8-1, a Catalyst 4500 series switch is connected to a balun through a short length of Cat5 UTP cable. Type 1/2 STP cable connects this balun to the next balun. Finally, another short length of Cat5 UTP cable connects the second balun to another Powered Device (e.g. Cisco IP phone).
Displaying the Operational Status for an Interface
Each interface has an operational status which reflects the PoE status for an interface. The operational status for an interface is defined as one of the following:
•on—Power is supplied by the port.
•off—Power is not supplied by the port. If a powered device is connected to an interface with external power, the switch does not recognize the powered device. The "Device" column in the show power inline command displays as n/a.
•Power-deny—The supervisor engine does not have enough power to allocate to the port, or the power that is configured for the port is less than the power required by the port; power is not being supplied by the port.
•err-disable—The port is unable to provide power to the connected device that is configured in static mode.
•faulty—The port failed diagnostics tests.
You can use the show power inline command to view the operational status for an interface.
This example shows how to display the operational status for all interfaces on module 3.
Switch# show power inline module 3
Available:677(w) Used:117(w) Remaining:560(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Fa3/1 auto on 17.3 15.4 Ieee PD 0
Fa3/2 auto on 4.5 4.0 Ieee PD 1
Fa3/3 auto on 7.1 6.3 Cisco IP Phone 7960 0
Fa3/4 auto on 7.1 6.3 Cisco IP Phone 7960 n/a
Fa3/5 auto on 17.3 15.4 Ieee PD 0
Fa3/6 auto on 17.3 15.4 Ieee PD 0
Fa3/7 auto on 4.5 4.0 Ieee PD 1
Fa3/8 auto on 7.9 7.0 Ieee PD 2
Fa3/9 auto on 17.3 15.4 Ieee PD 3
Fa3/10 auto on 17.3 15.4 Ieee PD 4
Fa3/11 auto off 0 0 n/a n/a
Fa3/12 auto off 0 0 n/a n/a
Fa3/13 auto off 0 0 n/a n/a
Fa3/14 auto off 0 0 n/a n/a
Fa3/15 auto off 0 0 n/a n/a
Fa3/16 auto off 0 0 n/a n/a
Fa3/17 auto off 0 0 n/a n/a
Fa3/18 auto off 0 0 n/a n/a
--------- ------ ---------- ---------- ---------- ------------------- -----
Totals: 10 on 117.5 104.6
Switch#
This example shows how to display the operational status for Fast Ethernet interface 4/1:
Switch#show power inline fa4/1
Available:677(w) Used:11(w) Remaining:666(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Fa4/1 auto on 11.2 10.0 Ieee PD 0
Interface AdminPowerMax AdminConsumption
(Watts) (Watts)
---------- --------------- --------------------
Fa4/1 15.4 10.0
Switch#
Displaying the PoE Consumed by a Module
The switch can measure the actual PoE consumption for an 802.3af-compliant PoE module, and it displays the measured PoE in both the show power module and show power detail commands. However, the switch cannot display the consumption of an individual interface on an 802.3af-compliant PoE module, nor can it measure the actual PoE consumption for the WS-X4148-RJ45V module. Therefore, for all PoE calculations, the PoE consumption on the WS-X4148-RJ45V module is presumed to be equal to its administrative PoE.
The 802.3af-compliant PoE modules can consume up to 20 W of PoE to power FPGAs and other hardware components on the module. Be sure to add at least 20 W to your PoE requirements for each 802.3af-compliant PoE module to ensure that the system has adequate power for the PDs connected to the switch.
The example below displays the PoE consumption for an 802.3af-compliant module using the show power module command.
The "Inline Power Oper" column displays the amount of PoE consumed by the powered devices that are attached to the module, in addition to the PoE consumed by the FPGAs and other hardware components on the module. The "Inline Power Admin" column displays only the amount of PoE allocated by the powered devices attached to the module.
Note The operating PoE consumption for an 802.3af-compliant module can be non-zero, even when there are no powered devices attached to the module, because of the PoE consumed by FPGAs and other hardware components on the module. In addition, the operating PoE can vary due to fluctuations in the PoE consumed by the hardware components.
Switch# show power module
Watts Used of System Power (12V)
Mod Model currently out of reset in reset
---- ----------------- --------- ------------ --------
1 WS-X4013+TS 330 330 330
2 WS-X4548-GB-RJ45V 60 60 20
3 WS-X4548-GB-RJ45V 60 60 20
-- Fan Tray 30 -- --
----------------------- --------- ------------ -------
Total 480 450 370
Watts used of Chassis Inline Power (-50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
2 WS-X4548-GB-RJ45V 138 123 73 65 89
3 WS-X4548-GB-RJ45V 0 0 22 20 89
----------------------- ---------------- ---------------- ----------
Total 138 123 95 85
Watts used of Module Inline Power (12V -> -50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
1 WS-X4013+TS 128 128 63 63 100
----------------------- ---------------- ---------------- ----------
switch#
The example below displays the PoE consumption for an 802.3af-compliant module using the show power detail and show power inline commands.
The "Inline Power Oper" column displays the amount of PoE consumed by the powered devices that are attached to the module, in addition to the PoE consumed by the FPGAs and other hardware components on the module. The "Inline Power Admin" column displays only the amount of PoE allocated by the powered devices attached to the module.
switch# show power detail
Power Fan Inline
Supply Model No Type Status Sensor Status
------ ---------------- --------- ----------- ------- -------
PS1 PWR-C45-1300ACV AC 1300W good good good
PS2 none -- -- -- --
Power supplies needed by system : 1
Power supplies currently available : 1
Power Summary Maximum
(in Watts) Used Available
---------------------- ---- ---------
System Power (12V) 480 1000
Inline Power (-50V) 138 800
Backplane Power (3.3V) 0 0
---------------------- ---- ---------
Total 618 (not to exceed Total Maximum Available = 1300)
Module Inline Power Summary (Watts)
(12V -> -48V on board conversion)
---------------------------------
Maximum
Mod Used Available
--- ---- ---------
1 128 158
--- ---- ---------
Watts Used of System Power (12V)
Mod Model currently out of reset in reset
---- ----------------- --------- ------------ --------
1 WS-X4013+TS 330 330 330
2 WS-X4548-GB-RJ45V 60 60 20
3 WS-X4548-GB-RJ45V 60 60 20
-- Fan Tray 30 -- --
----------------------- --------- ------------ -------
Total 480 450 370
Watts used of Chassis Inline Power (-50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
2 WS-X4548-GB-RJ45V 138 123 73 65 89
3 WS-X4548-GB-RJ45V 0 0 22 20 89
----------------------- ---------------- ---------------- ----------
Total 138 123 95 85
Watts used of Module Inline Power (12V -> -50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
1 WS-X4013+TS 128 128 64 64 100
----------------------- ---------------- ---------------- ----------
switch#
switch# show power inline g1/1
Module 1 Inline Power Supply: Available:158(w) Used:128(w) Remaining:30(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi1/1 auto on 10.3 10.3 CNU Platform 3
Interface AdminPowerMax AdminConsumption
(Watts) (Watts)
---------- --------------- --------------------
Gi1/1 15.4 15.4
sh power modiuswitch# show power inline g2/1
Chassis Inline Power Supply: Available:800(w) Used:138(w) Remaining:662(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi2/1 auto on 11.5 10.2 CNU Platform n/a
Interface AdminPowerMax AdminConsumption
(Watts) (Watts)
---------- --------------- --------------------
Gi2/1 15.4 15.4
switch#
switch#show power inline module 1
Module 1 Inline Power Supply: Available:158(w) Used:128(w) Remaining:30(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi1/1 auto on 10.3 10.3 CNU Platform 3
Gi1/2 auto on 10.3 10.3 CNU Platform 3
Gi1/3 auto on 10.3 10.3 CNU Platform 3
Gi1/4 auto on 10.3 10.3 CNU Platform 3
Gi1/5 auto on 10.3 10.3 CNU Platform 3
Gi1/6 auto on 10.3 10.3 CNU Platform 3
Gi1/7 auto on 10.3 10.3 CNU Platform 3
Gi1/8 auto on 10.3 10.3 CNU Platform 3
Gi1/9 auto on 10.3 10.3 CNU Platform 3
Gi1/10 auto on 15.4 15.4 Cisco/Ieee PD 3
Gi1/11 auto on 10.3 10.3 CNU Platform 3
Gi1/12 auto on 10.3 10.3 CNU Platform 3
--------- ------ ---------- ---------- ---------- ------------------- -----
Totals: 12 on 128.2 128.2
switch#
switch# show power inline module 2
Chassis Inline Power Supply: Available:800(w) Used:138(w) Remaining:662(w)
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi2/1 auto on 11.5 10.2 CNU Platform n/a
Gi2/2 auto on 11.5 10.2 CNU Platform n/a
Gi2/3 auto on 11.5 10.2 CNU Platform n/a
Gi2/4 auto on 11.5 10.2 CNU Platform n/a
Gi2/5 auto off 0.0 0.0 n/a n/a
Gi2/6 auto off 0.0 0.0 n/a n/a
Gi2/7 auto off 0.0 0.0 n/a n/a
Gi2/8 auto off 0.0 0.0 n/a n/a
Gi2/9 auto on 11.5 10.2 CNU Platform 3
Gi2/10 auto on 11.5 10.2 CNU Platform n/a
Gi2/11 auto on 11.5 10.2 CNU Platform n/a
Gi2/12 auto on 11.5 10.2 CNU Platform n/a
Gi2/13 auto on 11.5 10.2 CNU Platform 3
Gi2/14 auto on 11.5 10.2 CNU Platform 3
Gi2/15 auto on 11.5 10.2 CNU Platform 3
Gi2/16 auto on 11.5 10.2 CNU Platform 3
Gi2/17 auto off 0.0 0.0 n/a n/a
Gi2/18 auto off 0.0 0.0 n/a n/a
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi2/19 auto off 0.0 0.0 n/a n/a
Gi2/20 auto off 0.0 0.0 n/a n/a
Gi2/21 auto off 0.0 0.0 n/a n/a
Gi2/22 auto off 0.0 0.0 n/a n/a
Gi2/23 auto off 0.0 0.0 n/a n/a
Gi2/24 auto off 0.0 0.0 n/a n/a
Gi2/25 auto off 0.0 0.0 n/a n/a
Gi2/26 auto off 0.0 0.0 n/a n/a
Gi2/27 auto off 0.0 0.0 n/a n/a
Gi2/28 auto off 0.0 0.0 n/a n/a
Gi2/29 auto off 0.0 0.0 n/a n/a
Gi2/30 auto off 0.0 0.0 n/a n/a
Gi2/31 auto off 0.0 0.0 n/a n/a
Gi2/32 auto off 0.0 0.0 n/a n/a
Gi2/33 auto off 0.0 0.0 n/a n/a
Gi2/34 auto off 0.0 0.0 n/a n/a
Gi2/35 auto off 0.0 0.0 n/a n/a
Gi2/36 auto off 0.0 0.0 n/a n/a
Gi2/37 auto off 0.0 0.0 n/a n/a
Gi2/38 auto off 0.0 0.0 n/a n/a
Gi2/39 auto off 0.0 0.0 n/a n/a
Gi2/40 auto off 0.0 0.0 n/a n/a
Interface Admin Oper Power(Watts) Device Class
From PS To Device
--------- ------ ---------- ---------- ---------- ------------------- -----
Gi2/41 auto off 0.0 0.0 n/a n/a
Gi2/42 auto off 0.0 0.0 n/a n/a
Gi2/43 auto off 0.0 0.0 n/a n/a
Gi2/44 auto off 0.0 0.0 n/a n/a
Gi2/45 auto off 0.0 0.0 n/a n/a
Gi2/46 auto off 0.0 0.0 n/a n/a
Gi2/47 auto off 0.0 0.0 n/a n/a
Gi2/48 auto off 0.0 0.0 n/a n/a
--------- ------ ---------- ---------- ---------- ------------------- -----
Totals: 12 on 138.2 123.0
switch#
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