Users Guide

Figure 14. PSUs per grid and a power failure on grid 1
In the event of a single PSU failure in this conguration, the remaining PSUs in the failing grid are marked as Online. In this state, the PSUs
in the Redundant Grid if not in failed state, help in functioning of the system without interruption. If a PSU fails, the chassis health is
marked non-critical. If the smaller grid cannot support the total chassis power allocations, then grid redundancy status is reported as No
Redundancy and Chassis health is displayed as Critical.
Power Supply Redundancy Policy
The power supply redundancy policy is useful when redundant power grids are not available, but you may want to be protected against a
single PSU failure bringing down your servers in a modular enclosure. The highest capacity PSU is kept in online reserve for this purpose.
This forms a Power Supply redundancy pool. The gure below illustrates power supply redundancy mode.
PSUs beyond those required for power and redundancy are still available and are added to the pool if a failure occurs.
Unlike Grid Redundancy, when power supply redundancy is selected, CMC does not require the PSU units to be present in any specic
PSU slot positions.
NOTE
: Dynamic Power Supply Engagement (DPSE) allows PSUs to be placed in standby. The standby state indicates a physical
state during which power is not supplied from the PSU. When you enable DPSE, the extra PSUs may be placed in Standby mode
to increase eciency and save power.
Figure 15. Power Supply Redundancy: Totally 4 PSUs with a failure of one PSU
NOTE
: It is recommended to modify the modular enclosure Redundancy Policy while the enclosure is powered o.
No Redundancy Policy
The no redundancy mode is the factory default setting for three PSU conguration and indicates that the chassis does not have any power
redundancy congured. In this conguration, the overall redundancy status of the chassis always indicates no redundancy. The gure below
illustrates no redundancy mode is the factory default setting for three PSU conguration.
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Managing and Monitoring Power