Power Supply Redundancy - Cisco 6509 - Catalyst Chassis Switch Installation Manual

Appendix A Power Supply Specifications
In systems that are equipped with two power supplies, if one power supply fails and the other power
Note
supply cannot fully power all of the installed modules, system power management will shut down
devices in the following order:
Power over Ethernet (PoE) devices— The system will power down PoE devices in descending order,
•
starting with the highest numbered port on the module in the highest numbered slot.
Modules—If additional power savings are needed, the system will power down modules in
•
descending order, starting with the highest numbered slot. Slots containing supervisor engines or
Switch Fabric Modules are bypassed and are not powered down.
This shut down order is fixed and cannot be changed.
You can change the configuration of the power supplies to redundant or nonredundant at any time. If you
switch from a redundant to a nonredundant configuration, both power supplies are enabled (even a power
supply that was disabled because it was of a lower wattage than the other power supply). If you change
from a nonredundant to a redundant configuration, both power supplies are initially enabled, and if they
are of the same wattage, they remain enabled. If they are of different wattage, a syslog message displays
and the lower wattage supply is disabled.
For additional information about the power management feature and individual module power
consumption, refer to your software configuration guide.
OL-5781-04
Catalyst 6500 Series Switches Installation Guide

Power Supply Redundancy

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