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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.

  1. Make sure that the correct device drivers are installed and that they are at the latest level.
  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.

    • Make sure that the cable used is supported by the adapter. For more information about the supported adapters, cables, and transceivers of the specific servers, go to Compatibility for hardware, applications, and middleware.

    • Make sure that the cable rating is sufficient for the data rate of the network. For example, a 1 GB RJ45 network requires a cable of Cat5e or higher rating.

  3. Determine whether the switch supports auto-negotiation. If not, try configuring the integrated Ethernet controller manually to match the speed of the switch port. Also, if forward error correction (FEC) modes are supported, make sure that both the adapter and the switch port have matching settings.
  4. Check the Ethernet controller LEDs on the server. These LEDs indicate whether there is a problem with the connector, cable, or switch.

    If the Ethernet function is implemented on the system board (system board assembly), the Ethernet controller LED locations are specified in Troubleshooting by system LEDs and diagnostics display.

    • The Ethernet link status LED is lit when the Ethernet controller has established link with the switch port. If the LED is off, there might be a defective connector or cable or a problem with the switch port. In some cases, a bi-color link LED is used. Green indicates a link at the highest network speed. Yellow indicates a link lower than the highest network speed.

    • The Ethernet transmit/receive activity LED is lit or blinks when the Ethernet controller sends or receives data over the Ethernet network. If the Ethernet transmit/receive activity is off, make sure that the switch is powered on, the network is operating, and the correct device drivers are installed.

  5. Check for operating-system-specific causes of the problem, and make sure that the operating system drivers are installed correctly.
  6. Make sure that the device drivers on the client and server are using the same protocol.
If the Ethernet controller still cannot connect to the network but the hardware appears to be working, the network administrator must investigate other possible causes of the error.