Lenovo 7D31, Maintenance Manual

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• Memory modules until you reach the minimum configuration that is supported for the server.
Note:
For minimal configuration for debugging, see “Specifications” on page 2.
4. Power on the server.
If the problem is solved when you remove an adapter from the server, 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 server passes all system tests, suspect a network
cabling problem that is external to the server.
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 “Event logs” on page 221
Step 2. Check the power backplane LED to make sure it is lit (see “Power backplane connectors” on page
31). If not, press the switch to turn it on.
Step 3. Check for short circuits, for example, if a loose screw is causing a short circuit on a circuit board.
Step 4. Remove the adapters and disconnect the cables and power cords to all internal and external
devices until the server is at the minimum configuration that is required for the server to start. See
“Specifications” on page 2 to determine the minimum configuration for your server.
Step 5. 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 minimum configuration, see “Power supply LEDs” on page 224 to
replace the components in the minimum configuration one at a time until the problem is isolated.
Resolving suspected Ethernet controller problems
The method that you use to test the Ethernet controller depends on which operating system you are using.
See the operating-system documentation for information about Ethernet controllers, and see the Ethernet
controller device-driver readme file.
Complete the following steps to attempt to resolve suspected problems with the Ethernet controller.
Step 1. Make sure that the correct device drivers, which come with the server are installed and that they
are at the latest level.
Step 2. Make sure that the Ethernet cable is installed correctly.
• The cable must be securely attached at all connections. If the cable is attached but the problem
remains, try a different cable.
• If you set the Ethernet controller to operate at 100 Mbps or 1000 Mbps, you must use Category
5 cabling.
Step 3. Determine whether the hub supports auto-negotiation. If it does not, try configuring the integrated
Ethernet controller manually to match the speed and duplex mode of the hub.
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ThinkSystem SR850 V2 Maintenance Manual