Chapter 19 Initial Configuration - Dell PowerConnect J-EX4200-24T Software Manual

CHAPTER 19
Initial Configuration
Configuring Power Supply Redundancy (CLI Procedure)
Configuring Power Supply Redundancy (CLI Procedure) on page 307
Configuring the Power Priority of Line Cards (CLI Procedure) on page 308
By default, the power management feature in J-EX8200 switches is configured to manage
the power supplies for N+1 redundancy, in which one power supply is held in reserve for
backup if any one of the other power supplies is removed or fails.
You can configure power management to manage the power supplies for N+N
redundancy. For example, to set up your AC power supplies for dual power feed, N+N
redundancy is required. In N+N redundancy, power management allocates half of the
online power supplies to normal operating power and half to redundant power. If you
have an odd number of online power supplies, power management allocates one more
power supply to normal operating power than to redundant power.
This topic describes how to configure power management for N+N redundancy and how
to revert back to N+1 redundancy if your deployment needs change.
Before you configure power management for N+N redundancy, ensure that you have
sufficient power supplies to meet the power requirements of this configuration. Use the
show chassis power-budget-statistics
NOTE: To allow more power to be available to line cards, power management
compensates for the reduced normal operating power in an N+N configuration
by reserving less power to the chassis than it does in an N+1 configuration.
For the J-EX8208 switch, the power reserved for the chassis is reduced to
1200 W from 1600 W. For the J-EX8216 switch, it is reduced to 1800 W from
2400 W. In determining whether you have enough power for an N+N
configuration, take this reduction of reserved chassis power into account.
The reduction in reserved chassis power is achieved by reducing the maximum
fan speed to 60 percent in an N+N configuration from 80 percent in an N+1
configuration. Because the maximum fan speed is reduced, it is possible that
a line card that overheats would be shut down sooner in an N+N configuration
than in an N+1 configuration.
command to display your current power budget.
307