Solving undetermined problems

Use this information to solve undetermined problems.

Note: When you are diagnosing a problem in the compute node, you must determine whether the problem is in the compute node or in the Lenovo Flex System chassis.

If the Lenovo Flex System chassis contains more than one compute node and only one of the compute nodes has the problem, troubleshoot the compute node that has the problem.

If DSA did not diagnose the failure or if the compute node is inoperative, use the information in this section.

Corrupted data in CMOS memory or corrupted UEFI code can cause undetermined problems. To reset the CMOS data, remove and replace the CMOS battery to override the power-on password and clear the CMOS memory; see Removing the CMOS battery. If you suspect that the UEFI code is corrupted, see Recovering a UEFI image.

Check the LEDs on all the power supplies of the Lenovo Flex System chassis in which the compute node is installed. If the LEDs indicate that the power supplies are working correctly and reseating the compute node does not correct the problem, complete the following steps:
  1. If no LEDs on the control panel are working, try to turn on the compute node from the Chassis Management Module (see the documentation for the Lenovo Flex System chassis and Chassis Management Module for more information).
  2. Turn off the compute node.
  3. Remove the compute node from the Lenovo Flex System chassis and remove the cover.
  4. Remove or disconnect the following devices, one at a time, until you find the failure. Reinstall, turn on, and reconfigure the compute node each time.
    • I/O expansion adapter.
    • Hard disk drives.
    • DIMMs. The minimum configuration requirement is 4 GB (one 4 GB DIMM on the system board).

    The following minimum configuration is required for the compute node to start:

    • System board
    • Two microprocessors
    • One 4 GB DIMM
    • A functioning Lenovo Flex System chassis
  5. Install and turn on the compute node. If the problem remains, suspect the following components in the following order:
    1. DIMM
    2. System board
    3. Microprocessor

If the problem is solved when you remove an I/O expansion adapter from the compute node but the problem recurs when you reinstall the same adapter, suspect the I/O expansion adapter; if the problem recurs when you replace the adapter with a different one, suspect the system board.

If you suspect a networking problem and the compute node passes all the system tests, suspect a network cabling problem that is external to the system.

Parent topic: Troubleshooting