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Troubleshooting the chassis

If you experience problems with your Flex System Enterprise Chassis, there are several ways to isolate and solve the problem.

Using a management node

If a Lenovo XClarity Administrator or Flex System Manager management node is available, always use it as the starting point for troubleshooting the chassis. The management node communicates directly with the compute nodes and I/O modules and can aggregate status and logs from multiple chassis.

If no management node is available, you can use the Flex System Chassis Management Module (CMM) for troubleshooting.

If you are using a Flex System Manager management node, a failed CMM might not allow monitoring of chassis components. If a Flex System Manager is installed in a chassis without a working CMM, the Flex System Manager might not be able to reach the network to monitor other devices because it uses a network path through the CMM. For this reason, a chassis that contains a Flex System Manager should also contain two CMMs. The primary CMM automatically fails over to the standby CMM if there is a monitoring problem or a problem with the CMM.

Using the Flex System Chassis Management Module

Status information about fan modules, power supplies, and CMMs comes from the CMM. The CMM can also report some hardware errors on the I/O modules and compute nodes. The CMM is not operating-system aware and does not have information about device drivers.

The CMM allocates power to components and provides power permission to compute nodes if enough power is available. I/O modules are automatically powered on by the CMM if enough power is available. The CMM does not turn off power to I/O modules or compute nodes. The I/O modules and compute nodes have their own firmware that protects the hardware.

A service-level reset command is available in the CMM command-line interface that you can use to remotely cycle power to a monitored component. A service-level reset is a useful substitute for physically reseating a component, because it restarts the component without requiring physical access. See Lenovo Flex System Chassis Management Module service command for more information.

See also Lenovo Flex System Chassis Management Module service and support options.

Using the diagnostic LEDs

The front information panel has a fault (yellow) LED, a check log (yellow) LED, and an identify (blue) LED. If any LED is lit, it indicates that the chassis has power. Any lit yellow LED on the chassis indicates to log in to the highest level management device that is available (Flex System Manager management node or CMM) and read the event log. The identify LED is used to help identify the location of the failed component or chassis. Blue LEDs are always a result of a user action.