User's Manual

6 Carrier Grade Chassis Management Controller User’s Guide Addendum
For more information, see the External Power Management section in the
Chassis Management Controller Version 4.1 User’s Guide.
NOTE: Actual power delivery is based on configuration and workload.
The Power Management features of the M1000e help administrators
configure the enclosure to reduce power consumption and to customize
power management to their unique requirements and environments. You can
configure the PowerEdge M1000e enclosure for any of three redundancy
policies that affect PSU behavior and determine how chassis Redundancy
state is reported to administrators.
Grid Redundancy Mode
The purpose of the Grid redundancy policy is to enable a modular enclosure
system to operate in a mode in which it can tolerate input power failures.
These failures may originate in the input power grid, the cabling and delivery,
or a PSU itself.
When you configure a system for Grid redundancy, the PSUs are divided into
grids: PSUs in slots 1, 2, and 3 are in the first grid while PSUs in slots 4, 5, and
6 are in the second grid. CMC manages power so that if there is a failure of
either grid the system continues to operate without any degradation. Grid
redundancy also tolerates failures of individual PSUs.
NOTE: Since one role of Grid redundancy is to provide seamless server operation
despite failure of a whole power grid, the most power is available to maintain Grid
redundancy when the capacities of the two grids are approximately equal.
NOTE: Grid redundancy is only met when the load requirements do not exceed the
capacity of the weakest power grid.
Grid Redundancy Levels
One PSU in each grid is the minimum configuration necessary for use as grid
redundant. Additional configurations are possible with every combination
that has at least one PSU in each grid. However, to make the maximum power
available for use, the total power of the PSUs in each grid should be as close
to equal as practical. The upper limit of power available to the M1000e while
maintaining grid redundancy is the power available on the weaker of the two
grids. Figure 1-1 illustrates two PSUs per grid and a power failure on grid 1. If