Users Guide

First Steps to Troubleshoot a Remote System
The following questions are commonly used to troubleshoot high-level problems in the managed system:
• Is the system powered on or o?
• If powered on, is the operating system functioning, crashed, or frozen?
• If powered o, did the power turn o unexpectedly?
Power Troubleshooting
The following information helps you to troubleshoot power supply and power-related issues:
• Problem: Congured the Power Redundancy Policy to Grid Redundancy, and a Power Supply Redundancy Lost event was raised.
– Resolution A: This conguration requires at least one power supply in side 1 (the left three slots) and one power supply in side 2
(the right three slots) to be present and functional in the modular enclosure. Additionally the capacity of each side must be enough
to support the total power allocations for the chassis to maintain Grid Redundancy. (For full Grid Redundancy operation, ensure
that a full PSU conguration of six power supplies is available.)
– Resolution B: Ensure that all power supplies are properly connected to the two AC grids. Power supplies in side 1 need to be
connected to one AC grid, those in side 2 need to be connected to the other AC grid, and both AC grids must be working. Grid
Redundancy
is lost when one of the AC grids is not functioning.
• Problem: The PSU state is displayed as Failed (No AC), even when an AC cable is connected and the power distribution unit is
producing good AC output.
– Resolution A: Check and replace the AC cable. Check and conrm that the power distribution unit providing power to the power
supply is operating as expected. If the failure still persists, call Dell customer service for replacement of the power supply.
– Resolution B: Check that the PSU is connected to the same voltage as the other PSUs. If CMC detects a PSU operating at a
dierent voltage, the PSU is turned o and marked Failed.
• Problem: Dynamic Power Supply Engagement is enabled, but none of the power supplies display in the Standby state.
– Resolution A: There is insucient surplus power. One or more power supplies are moved into the Standby state only when the
surplus power available in the enclosure exceeds the capacity of at least one power supply.
– Resolution B: Dynamic Power Supply Engagement cannot be fully supported with the power supply units present in the enclosure.
To check if this is the case, use the Web interface to turn Dynamic Power Supply Engagement o, and then on again. A message
is displayed if Dynamic Power Supply Engagement cannot be fully supported.
• Problem: Installed a new server into the enclosure with sucient power supplies, but the server does not power on.
– Resolution A: Ensure that the system input power cap setting is not congured too low to allow any additional servers to be
powered up.
– Resolution B: Check for 110V operation. If any power supplies are connected to 110V branch circuits, you must acknowledge this as
a valid conguration before servers are allowed to power on. For more details, see the power conguration settings.
– Resolution C: Check the maximum power conservation setting. If this is set then servers are allowed to power on. For more details,
see the power conguration settings.
– Resolution D: Ensure that the server slot power priority of the slot associated with the newly installed server, is not lower than any
other server slot power priority.
• Problem: Available power keeps changing, even when the modular enclosure conguration has not changed
– Resolution: CMC 1.2 and later versions have dynamic fan power management that reduces server allocations briey if the
enclosure is operating near the peak user congured power cap. It causes the fans to be allocated power by reducing server
performance to keep the input power drawn below System Input Power Cap. This is normal behavior.
• Problem: 2000 W is reported as the Surplus for Peak Performance.
– Resolution: The enclosure has 2000 W of surplus power available in the current conguration, and the System Input Power Cap
can be safely reduced by this amount being reported without impacting server performance.
• Problem: A subset of servers lost power after an AC Grid failure, even when the chassis was operating in the Grid Redundancy
conguration with six power supplies.
– Resolution: This can occur if the power supplies are improperly connected to the redundant AC grids at the time the AC grid failure
occurs. The Grid Redundancy policy requires that the left three power supplies are connected to one AC Grid, and right three
Troubleshooting and Recovery
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