User's Manual

14 Carrier Grade Chassis Management Controller User’s Guide Addendum
• In a No Redundancy configuration with DPSE, the M1000e can have up to
five power supply units in Standby state. In a six PSU configuration, some
PSU units are placed in Standby and are not utilized to improve power
efficiency. Removal or failure of an online PSU in this configuration cause
a PSU in Standby state to change to Online; however, standby PSUs can
take up to two seconds to become active, so some server modules may lose
power during the transition in the No Redundancy configuration.
NOTE: In a three PSU configuration, server load may prevent any PSUs from
transitioning to Standby.
• In a Power Supply Redundancy configuration, the enclosure always keeps
an additional PSU powered on and marked Online in addition to the PSUs
required to power the enclosure. Power utilization is monitored and up to
four PSUs could be moved to Standby state depending on the overall
system load. In a six PSU configuration, a minimum of two power supply
units are always powered on.
Since an enclosure in the Power Supply Redundancy configuration always
has an extra PSU engaged, the enclosure can tolerate the loss of one online
PSU and still have enough power for the installed server modules. The loss
of the online PSU causes a standby PSU to come online. Simultaneous
failure of multiple PSUs may result in the loss of power to some server
modules while the standby PSUs are powering up.
• In Grid Redundancy configuration, all power supplies are engaged at
chassis power up. Power utilization is monitored, and if system
configuration and power utilization allows, PSUs are moved to the
Standby state. Since the Online status of PSUs in a grid mirrors that of the
other grid, the enclosure can sustain the loss of power to an entire grid
with no interruption of power to the enclosure.
An increase in power demand in the Grid Redundancy configuration
causes the engagement of PSUs from the Standby state. This maintains
the mirrored configuration needed for dual-grid redundancy.
NOTE: With DPSE Enabled, the Standby PSUs are brought Online to reclaim power
if power demand increases in all three Power Redundancy policy modes.