Power Supply Modes - Cisco Catalyst 9400 Series Hardware Installation Manual

Product Overview
Module
Fan Tray, Supervisor Module, Backplane
(Standby Output)

Power Supply Modes

Cisco Catalyst 9400 Series Switches offer redundant and combined configuration modes for power supplies.
The number of power supply modules installed and the system load determine the power level that the system
expects to draw from each power supply module, and consequently, the power supply mode that will be
suitable. To calculate, or estimate a system's power budget, and to determine power supply requirements for
a specific PoE configuration, use the
To configure a power supply mode, enter the power redundancy-mode command in global configuration
mode. If you do not configure a mode, the default mode is applicable.
Combined Mode
This is the default power supply mode.
The system operates on one to eight power supply modules. The power available to the system is the sum of
power outputs of all the power supply modules in the chassis. All available power supply modules are active,
share power, and can operate at up to 100 percent capacity.
Caution
When operating in combined mode, if any of the modules fail, all remaining operational power supply modules
increase their output. If the output power does not meet the system requirements and the power supply autolc
shutdown command is disabled, all the operational power supply modules may get overloaded and go into
overcurrent shutdown. All system power is then lost.
Redundant Mode
In a redundant configuration, a given power supply module can either be active, or in standby:
• An active power supply module is powered on, and provides output power. All the active modules in a
• A standby power supply module is powered on, but asleep, and can switch to active when required. When
To ensure high availability, the system is designed to respond to failure as follows:
• If all the available power supply modules are active, the operational power supplies continue to share
• If standby power supply modules are available, the minimum number of power supply modules needed
When configuring a redundant mode, you have these options: an n+1 or an n+n redundant mode.
N+1 Redundant Mode
chassis always attempt to share the load.
in standby mode, the power supply module's OUTPUT LED is blinking green.
current equally. Note that the load on the available power supplies would have increased.
to power the load switch to active.
C9400-PWR-2100AC, C9400-PWR-3200AC, and
C9400-PWR-3200DC
3.3 VDC
Cisco Power Calculator.
Cisco Catalyst 9400 Series Switches Hardware Installation Guide
Power Supply Modes
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