General Problem Determination Procedures; Resolving Suspected Power Problems - Lenovo ThinkSystem SD550 V3 User Manual

General problem determination procedures

Use the information in this section to resolve problems if the event log does not contain specific errors or the
system is inoperative.
If you are not sure about the cause of a problem and the power supplies are working correctly, complete the
following steps to attempt to resolve the problem:
1. Power off the system.
2. Make sure that the system is cabled correctly.
3. Remove or disconnect the following devices if applicable, one at a time, until you find the failure. Power
on and configure the system each time you remove or disconnect a device.
• Any external devices.
• Surge-suppressor device (on the system).
• Printer, mouse, and non-Lenovo devices.
• Each adapter.
• Hard disk drives.
• Memory modules until you reach the minimum configuration that is supported for the system.
Note: To determine the minimal configuration for your system, see "Minimal configuration for
debugging" in "Node technical specifications" on page
4. Power on the system.
If the problem is solved when you remove an adapter from the node, but the problem recurs when you install
the same adapter again, suspect the adapter. If the problem recurs when you replace the adapter with a
different one, try a different PCIe slot.
If the problem appears to be a networking problem and the compute node passes all system tests, suspect a
network cabling problem that is external to the node.

Resolving suspected power problems

Power problems can be difficult to solve. For example, a short circuit can exist anywhere on any of the power
distribution buses. Usually, a short circuit will cause the power subsystem to shut down because of an
overcurrent condition.
Complete the following steps to diagnose and resolve a suspected power problem.
Step 1. Check the event log and resolve any errors related to the power.
Note: Start with the event log of the application that is managing the server. For more information
about event logs, see
Step 2. Check for short circuits, for example, if a loose screw is causing a short circuit on a circuit board.
Step 3. Remove the adapters and disconnect the cables and power cords to all internal and external
devices until the server is at the minimal configuration for debugging that is required for the server
to start. To determine the minimal configuration for your server, see "Minimal configuration for
debugging" in
Step 4. Reconnect all AC power cords and turn on the server. If the server starts successfully, reseat the
adapters and devices one at a time until the problem is isolated.
If the server does not start from the minimal configuration, replace the components in the minimal
configuration one at a time until the problem is isolated.
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"Event logs" on page
"Node technical specifications" on page
10.
249.
6.