Result
Reserve
Power
Available
Power
Power
Supply 2
Output
Power
Supply 1
Output
Power
Requirement
Scenario
Available
power
exceeds the
power
requirement
for the
switch, so the
entire switch
can power
up.
—
6.0 kW
3.0 kW
3.0 kW
5.2 kW
2
Power supply (n+1) redundancy mode
The power supply that outputs the most power provides the reserve power so that it can take over for
any other power supply that fails, and all of the other installed power supplies provide the available
power. You activate this power mode by using the
power redundancy-mode ps-redundant
command.
For example, if the power requirement for a switch is 5.2 kW and the switch has two 3.0 kW power
supplies outputting 3.0 kW each (220-V input from the grid), consider the following power planning
scenarios:
• Scenario 1—no added power supplies
One 3-kW power supply, which outputs just 3.0 kW for 110-V of input power, provides the reserve
power and the other 3-kW power supply, also outputting 3.0 kW, provides the available power. The
available power (3.0 kW) does not meet the switch requirements of 5.2 kW, so the switch powers
up except for some of its I/O modules.
• Scenario 2—adding one 3-kW power supply
One 3-kW power supply, which outputs 1.45 kW, provides the reserve power and the other two
3-kW power supplies, also outputting 3.0 kW each, provide a sufficient amount of power (6.0 kW)
to meet the switch requirements (5.2 kW), so the entire switch powers up.
The following table shows the results for each scenario.
Cisco Nexus 7710 Switch Site Preparation and Hardware Installation Guide
73
OL-30452-01.
Managing the Switch
Guidelines for Configuring Power Redundancy Modes