Power Management

Note ● For complete syntax and usage information for the commands used in this chapter, see these publications:

http://www.cisco.com/en/US/products/ps11846/prod_command_reference_list.html

  • Cisco IOS Release 15.1SY supports only Ethernet interfaces. Cisco IOS Release 15.1SY does not support any WAN features or commands.

 

Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information), see the documents listed on this page:

http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html

Participate in the Technical Documentation Ideas forum

 

Power Management Overview

In systems with redundant power supplies, both power supplies must be of the same wattage. The Catalyst 6500 series switches allow you to use both AC-input and DC-input power supplies in the same chassis. For detailed information on supported power supply configurations, see the Catalyst 6500 Series Switch Installation Guide.

The modules have different power requirements, and some configurations require more power than a single power supply can provide. The power management feature allows you to power all installed modules with two power supplies. However, redundancy is not supported in this configuration because the total power drawn from both power supplies is at no time greater than the capability of one supply. Redundant and nonredundant power configurations are described in the following sections.

How to Enable or Disable Power Redundancy

To disable or enable redundancy (redundancy is enabled by default) from global configuration mode, enter the power redundancy-mode combined | redundant commands. You can change the configuration of the power supplies to redundant or nonredundant at any time.

To disable redundancy, use the combined keyword. In a nonredundant configuration, the power available to the system is the combined power capability of both power supplies. The system powers up as many modules as the combined capacity allows. However, if one power supply fails and there is not enough power for all of the previously powered-up modules, the system powers down those modules.

To enable redundancy, use the redundant keyword. In a redundant configuration, the total power drawn from both power supplies is not greater than the capability of one power supply. If one supply malfunctions, the other supply can take over the entire system load. When you install and power up two power supplies, each concurrently provides approximately half of the required power to the system. Load sharing and redundancy are enabled automatically; no software configuration is required.

To view the current state of modules and the total power available for modules, enter the show power command (see the “How to Display System Power Status” section).

Table 1-1 describes how the system responds to changes in the power supply configuration.

 

Table 1-1 Effects of Power Supply Configuration Changes

Configuration Change
Effect

Redundant to nonredundant
  • System log and syslog messages are generated.
  • System power is increased to the combined power capability of both power supplies.
  • Modules marked power-deny in the show power oper state field are brought up if there is sufficient power.

Nonredundant to redundant (both power supplies must be of equal wattage)
  • System log and syslog messages are generated.
  • System power is decreased to the power capability of one supply.
  • If there is not enough power for all previously powered-up modules, some modules are powered down and marked as power-deny in the show power oper state field.

Equal wattage power supply is inserted with redundancy enabled
  • System log and syslog messages are generated.
  • System power equals the power capability of one supply.
  • No change in module status because the power capability is unchanged.

Equal wattage power supply is inserted with redundancy disabled
  • System log and syslog messages are generated.
  • System power is increased to the combined power capability of both power supplies.
  • Modules marked power-deny in the show power oper state field are brought up if there is sufficient power.

Higher or lower wattage power supply is inserted with redundancy enabled
  • System log and syslog messages are generated.
  • If the system power used is more than 83% of the higher wattage power supply capacity, the lower wattage power supply shuts down. The system will operate in redundant mode, with only the higher wattage power supply.
  • If the system power used is less than 83% of the higher wattage power supply capacity, the lower wattage power supply comes online. The system will operate in non-redundant combined mode, with both the power supplies.

Higher or lower wattage power supply is inserted with redundancy disabled
  • System log and syslog messages are generated.
  • System power is increased to the combined power capability of both power supplies.
  • Modules marked power-deny in the show power oper state field are brought up if there is sufficient power.

Power supply is removed with redundancy enabled
  • System log and syslog messages are generated.
  • No change in module status because the power capability is unchanged.

Power supply is removed with redundancy disabled
  • System log and syslog messages are generated.
  • System power is decreased to the power capability of one supply.
  • If there is not enough power for all previously powered-up modules, some modules are powered down and marked as power-deny in the show power oper state field.

System is booted with power supplies of different wattage installed and redundancy enabled
  • System log and syslog messages are generated.
  • If the system power used is more than 83% of the higher wattage power supply capacity, the lower wattage power supply shuts down. The system will operate in redundant mode, with only the higher wattage power supply.
  • If the system power used is less than 83% of the higher wattage power supply capacity, the lower wattage power supply comes online. The system will operate in non-redundant combined mode, with both the power supplies.

System is booted with power supplies of equal or different wattage installed and redundancy disabled
  • System log and syslog messages are generated.
  • System power equals the combined power capability of both power supplies.
  • The system powers up as many modules as the combined capacity allows.

How to Power Modules Off and On

To power modules off and on from the CLI, perform this task:

 

Command
Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# power enable module slot_number

Powers a module on.

Step 3

Router(config)# no power enable module slot_number

Powers a module off.

Note When you enter the no power enable module slot command to power down a module, the module’s configuration is not saved.

This example shows how to power on the module in slot 3:

Router# configure terminal
Router(config)# power enable module 3

How to Display System Power Status

The show power command displays the current power status of system components:

Router# show power
system power redundancy mode = redundant
system power redundancy operationally = non-redundant
system power total = 3795.12 Watts (90.36 Amps @ 42V)
system power used = 864.78 Watts (20.59 Amps @ 42V)
system power available = 2930.34 Watts (69.77 Amps @ 42V)
Power-Capacity PS-Fan Output Oper
PS Type Watts A @42V Status Status State
---- ------------------ ------- ------ ------ ------ -----
1 none
2 WS-CAC-4000W-US 3795.12 90.36 OK OK on
Pwr-Allocated Oper
Fan Type Watts A @42V State
---- ------------------ ------- ------ -----
1 WS-C6506-E-FAN 140.70 3.35 OK
Pwr-Requested Pwr-Allocated Admin Oper
Slot Card-Type Watts A @42V Watts A @42V State State
---- ------------------ ------- ------ ------- ------ ----- -----
5 (Redundant Sup) - - 362.04 8.62 - -
6 VS-SUP2T-10G 362.04 8.62 362.04 8.62 on on
system auxiliary power mode = off
system auxiliary power redundancy operationally = non-redundant
system primary connector power limit = 7266.00 Watts (173.00 Amps @ 42V)
system auxiliary connector power limit = 10500.00 Watts (250.00 Amps @ 42V)
system primary power used = 864.78 Watts (20.59 Amps @ 42V)
system auxiliary power used = 0 Watt
 
Router#
 

The show power command displays the current power status of a specific power supply:

Router# show power status power-supply 2
Power-Capacity PS-Fan Output Oper
PS Type Watts A @42V Status Status State
---- ------------------ ------- ------ ------ ------ -----
2 WS-CAC-4000W-US 3795.12 90.36 OK OK on
Router#
 

You can display power supply input fields by specifying the power supply number in the command. A new power-output field with operating mode is displayed for power supplies with more than one output mode. Enter the show environment status power-supply command as follows:

Router# show environment status power-supply 1
power-supply 1:
power-supply 1 fan-fail: OK
power-supply 1 power-input 1: AC low
power-supply 1 power-output-fail: OK
Router# show environment status power-supply 2
power-supply 2:
power-supply 2 fan-fail: OK
power-supply 2 power-input 1: none
power-supply 2 power-input 2: AC low
power-supply 2 power-input 3: AC high
power-supply 2 power-output: low (mode 1)<<< high for highest mode only
power-supply 2 power-output-fail: OK

How to Power Cycle Modules

You can power cycle (reset) a module from global configuration mode by entering the power cycle module slot command. The module powers off for 5 seconds, and then powers on.

Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information), see the documents listed on this page:

http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html

Participate in the Technical Documentation Ideas forum